What does the word combination mean

Princeton’s WordNetRate this definition:4.2 / 6 votes

1. combinationnoun

   a collection of things that have been combined; an assemblage of separate parts or qualities

2. combinationnoun

   a coordinated sequence of chess moves

3. combinationnoun

   a sequence of numbers or letters that opens a combination lock

   «he forgot the combination to the safe»

4. combinationnoun

   a group of people (often temporary) having a common purpose

   «they were a winning combination»

5. combinationnoun

   an alliance of people or corporations or countries for a special purpose (formerly to achieve some antisocial end but now for general political or economic purposes)

6. combinationnoun

   the act of arranging elements into specified groups without regard to order

7. combination, combining, compoundingnoun

   the act of combining things to form a new whole

WiktionaryRate this definition:0.0 / 0 votes

1. combinationnoun

   The act of combining, the state of being combined or the result of combining.

2. combinationnoun

   A sequence of numbers or letters used to open a combination lock.

3. combinationnoun

   One or more elements selected from a set without regard to the order of selection.

4. combinationnoun

   An association or alliance of people for some common purpose.

5. combinationnoun

   A combination shot; a billiard; a shot where the cue ball hits a ball that strikes another ball on the table.

Samuel Johnson’s DictionaryRate this definition:0.0 / 0 votes

1. Combinationnoun

   Etymology: from combine.

   1. Union for some certain purpose; association; league. A combination is of private persons, a confederacy of states or sovereigns.

   This cunning cardinal
   The articles o’ th’ combination drew,
   As himself pleas’d.
   William Shakespeare, Henry VIII.

   2. It is now generally used in an ill sense; but was formerly indifferent.

   They aim to subdue all to their own will and power, under the disguises of holy combinations.
   Charles I .

   3. Union of bodies, or qualities; commixture; conjunction.

   These natures, from the moment of their first combination, have been and are for ever inseparable.
   Richard Hooker, b. v. s. 52.

   Resolution of compound bodies by fire, does not so much enrich mankind as it divides the bodies; as upon the score of its making new compounds by new combinations.
   Boyle.

   Ingratitude is always in combination with pride and hard-heartedness.
   Robert South, Sermons.

   4. Copulation of ideas in the mind.

   They never suffer any ideas to be joined in their understandings, in any other or stronger combination than what their own nature and correspondence give them.
   John Locke.

   5.Combination is used in mathematicks, to denote the variation or alteration of any number of quantities, letters, sounds, or the like, in all the different manners possible. thus the number of possible changes or combinations of the twenty-four letters of the alphabet, taken first two by two, then three by three, &c. amount to 1,391,724,288,887,252,999,425,128,493,402,200. Ephraim Chambers

Webster DictionaryRate this definition:1.0 / 1 vote

1. Combinationnoun

   the act or process of combining or uniting persons and things

2. Combinationnoun

   the result of combining or uniting; union of persons or things; esp. a union or alliance of persons or states to effect some purpose; — usually in a bad sense

3. Combinationnoun

   the act or process of uniting by chemical affinity, by which substances unite with each other in definite proportions by weight to form distinct compounds

4. Combinationnoun

   the different arrangements of a number of objects, as letters, into groups

FreebaseRate this definition:0.0 / 0 votes

1. Combination

   In mathematics a combination is a way of selecting several things out of a larger group, where order does not matter. In smaller cases it is possible to count the number of combinations. For example given three fruit, say an apple, orange and pear, there are three combinations of two that can be drawn from this set: an apple and a pear; an apple and an orange; or a pear and an orange. More formally a k-combination of a set S is a subset of k distinct elements of S. If the set has n elements the number of k-combinations is equal to the binomial coefficient
   which can be written using factorials as whenever, and which is zero when . The set of all k-combinations of a set S is sometimes denoted by .
   Combinations can refer to the combination of n things taken k at a time without or with repetitions. In the above example repetitions were not allowed. If however it was possible to have two of any one kind of fruit there would be 3 more combinations: one with two apples, one with two oranges, and one with two pears.
   With large sets, it becomes necessary to use more sophisticated mathematics to find the number of combinations. For example, a poker hand can be described as a 5-combination of cards from a 52 card deck. The 5 cards of the hand are all distinct, and the order of cards in the hand does not matter. There are 2,598,960 such combinations, and the chance of drawing any one hand at random is 1 / 2,598,960.

Editors ContributionRate this definition:0.0 / 0 votes

1. combination

   To combine into a whole.

   There are a perfect combination of personalities and it is such joyful news to know they are getting married.

   Submitted by MaryC on March 17, 2020  

Matched Categories

1. • Alliance
   • Change Of Integrity
   • Collection
   • Mathematical Process
   • Politics
   • Sequence
   • Unit

British National Corpus

1. Spoken Corpus Frequency

   Rank popularity for the word ‘combination’ in Spoken Corpus Frequency: #2275

2. Written Corpus Frequency

   Rank popularity for the word ‘combination’ in Written Corpus Frequency: #4319

3. Nouns Frequency

   Rank popularity for the word ‘combination’ in Nouns Frequency: #861

How to pronounce combination?

How to say combination in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of combination in Chaldean Numerology is: 4

2. Pythagorean Numerology

   The numerical value of combination in Pythagorean Numerology is: 7

Examples of combination in a Sentence

1. Conductor Ludwig Wicki:

   For me it’s a combination of music and horses and landscapes. When I was young I dreamed to be a cowboy, and I think that’s what Western is, it’s a dream for mostly boys, to be a cowboy or an Indian, and have these beautiful clothes, we played that in the forest, and that’s still in my heart.

2. Gwen Stefani:

   I wonder … it’s the combination. It’s the chemistry.

3. Rick Molinari:

   You might think you’re tipsy, but it’s the combination of the sugar and the caffeine.

4. Nikita Shah:

   Patients willsay I started taking tamoxifen and I gained 40 pounds, but that’s probably a combination of hormonal and lifestyle changes they’re going through. Tamoxifen can cause some fluid retention, and it could maybe cause a 2- or 3-pound weight gain, but beyond that there are probably other things going on as well.

5. Kate Larsen:

   In an ideal world you use both to have the most efficient outcome, some combination of those two approaches is really going to be what’s most effective at deploying clean generation at the scale we need.

Popularity rank by frequency of use

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Translations for combination

From our Multilingual Translation Dictionary

• مزيجArabic
• съединение, комбинация, обединениеBulgarian
• combinacióCatalan, Valencian
• kombinaceCzech
• Kombination, VereinigungGerman
• τρίκυκλοGreek
• combinaciónSpanish
• sobitama, järjestus, kombinatsioon, kooslus, kombineerimaEstonian
• ترکیبPersian
• ratsastus, kombinaatio, yhdistäminen, yhdistely, yhdistelmä, yhdistysFinnish
• combinaisonFrench
• combinaciónGalician
• संयोगHindi
• combinazioneItalian
• 統合, 結合, 合併Japanese
• combinatioLatin
• kombinasjonNorwegian
• vereniging, verbinding, combinatieDutch
• kombinasjonNorwegian Nynorsk
• combinaçãoPortuguese
• combinație, combinareRomanian
• сочетание, объединение, соединение, комбинацияRussian
• kombinering, kombinationSwedish
• birlik, dernek, birleşim, cemiyet, kombinasyon, birleştirmeTurkish

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Last Update: Jan 03, 2023

This is a question our experts keep getting from time to time. Now, we have got the complete detailed explanation and answer for everyone, who is interested!

Asked by: Brennon Lang

Score: 4.8/5
(71 votes)

In mathematics, a combination is a selection of items from a collection, such that the order of selection does not matter.

What does any combination mean?

a collection of things that have been combined; an assemblage of separate parts or qualities. combinationnoun.

What is word combination?

Many scientific words are based either on combinations of prefixes/suffixes of Greek, Latin, Indo-European or other origin linked to descriptive words or are combinations of short independent words included together as part of descriptive phrases.

What is combination with example?

A combination is a selection of all or part of a set of objects, without regard to the order in which objects are selected. For example, suppose we have a set of three letters: A, B, and C. … Each possible selection would be an example of a combination. The complete list of possible selections would be: AB, AC, and BC.

What does combinations mean in math?

A combination is a mathematical technique that determines the number of possible arrangements in a collection of items where the order of the selection does not matter. In combinations, you can select the items in any order.

23 related questions found

комбинация, сочетание, соединение, объединение, совмещение, союз

существительное ↓

Словосочетания

a combination of intrinsic and extrinsic factors — сочетание внутренних и внешних факторов  
a heady combination of wine and brandy — пьянящее сочетание вина и коньяка  
combination tanned leather — кожа комбинированного дубления  
combination room — профессорская  
business combination — объединение компаний, слияние компаний  
combination block — комбинированное клише (растровое и штриховое)  
forbidden-combination check — контроль по запрещенным комбинациям  
cipher combination — комбинация шифра  
ciphertext combination — комбинация (группа знаков) шифротекста  
code combination — кодовая комбинация  
bit combination — набор двоичных знаков  
a combination of both — и тот, и другой  

Примеры с переводом

Примеры, ожидающие перевода

Возможные однокоренные слова

Формы слова

noun
ед. ч.(singular): combination
мн. ч.(plural): combinations

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I’m an incurable romantic, and Casablanca’s one of the most romantic pictures I’ve ever seen — the combination of Bogart and Bergman is just magical.

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PRONUNCIATION OF COMBINATION

GRAMMATICAL CATEGORY OF COMBINATION

Combination is a noun.

WHAT DOES COMBINATION MEAN IN ENGLISH?

Definition of combination in the English dictionary

The first definition of combination in the dictionary is the act of combining or state of being combined. Other definition of combination is a union of separate parts, qualities, etc. Combination is also an alliance of people or parties; group having a common purpose.

WORDS THAT RHYME WITH COMBINATION

SYNONYMS OF «COMBINATION»

The following words have a similar or identical meaning as «combination» and belong to the same grammatical category.

TRANSLATION OF COMBINATION

Find out the translation of combination to 25 languages with our English multilingual translator.

TENDENCIES OF USE OF THE TERM «COMBINATION»

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Principal search tendencies and common uses of combination

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REFERENCE

« EDUCALINGO. Combination [online]. Available <https://educalingo.com/en/dic-en/combination>. Apr 2023 ».

What does Combination Mean?

Last Updated:
14 Apr 2023
— Updated example sentences

This article is about the mathematics of selecting part of a collection. For other uses, see Combination (disambiguation).

In mathematics, a combination is a selection of items from a set that has distinct members, such that the order of selection does not matter (unlike permutations). For example, given three fruits, say an apple, an orange and a pear, there are three combinations of two that can be drawn from this set: an apple and a pear; an apple and an orange; or a pear and an orange. More formally, a k—combination of a set S is a subset of k distinct elements of S. So, two combinations are identical if and only if each combination has the same members. (The arrangement of the members in each set does not matter.) If the set has n elements, the number of k-combinations, denoted by or , is equal to the binomial coefficient

which can be written using factorials as whenever , and which is zero when . This formula can be derived from the fact that each k-combination of a set S of n members has permutations so or .^[1] The set of all k-combinations of a set S is often denoted by .

A combination is a combination of n things taken k at a time without repetition. To refer to combinations in which repetition is allowed, the terms k-combination with repetition, k-multiset,^[2] or k-selection,^[3] are often used.^[4] If, in the above example, it were possible to have two of any one kind of fruit there would be 3 more 2-selections: one with two apples, one with two oranges, and one with two pears.

Although the set of three fruits was small enough to write a complete list of combinations, this becomes impractical as the size of the set increases. For example, a poker hand can be described as a 5-combination (k = 5) of cards from a 52 card deck (n = 52). The 5 cards of the hand are all distinct, and the order of cards in the hand does not matter. There are 2,598,960 such combinations, and the chance of drawing any one hand at random is 1 / 2,598,960.

Number of k-combinations[edit]

The number of k-combinations from a given set S of n elements is often denoted in elementary combinatorics texts by , or by a variation such as , , , or even (the last form is standard in French, Romanian, Russian, Chinese^[5][6] and Polish texts^{[citation needed]}). The same number however occurs in many other mathematical contexts, where it is denoted by (often read as «n choose k«); notably it occurs as a coefficient in the binomial formula, hence its name binomial coefficient. One can define for all natural numbers k at once by the relation

from which it is clear that

and further,

for k > n.

To see that these coefficients count k-combinations from S, one can first consider a collection of n distinct variables X_s labeled by the elements s of S, and expand the product over all elements of S:

it has 2ⁿ distinct terms corresponding to all the subsets of S, each subset giving the product of the corresponding variables X_s. Now setting all of the X_s equal to the unlabeled variable X, so that the product becomes (1 + X)ⁿ, the term for each k-combination from S becomes X^k, so that the coefficient of that power in the result equals the number of such k-combinations.

Binomial coefficients can be computed explicitly in various ways. To get all of them for the expansions up to (1 + X)ⁿ, one can use (in addition to the basic cases already given) the recursion relation

for 0 < k < n, which follows from (1 + X)ⁿ = (1 + X)^{n − 1}(1 + X); this leads to the construction of Pascal’s triangle.

For determining an individual binomial coefficient, it is more practical to use the formula

The numerator gives the number of k-permutations of n, i.e., of sequences of k distinct elements of S, while the denominator gives the number of such k-permutations that give the same k-combination when the order is ignored.

When k exceeds n/2, the above formula contains factors common to the numerator and the denominator, and canceling them out gives the relation

for 0 ≤ k ≤ n. This expresses a symmetry that is evident from the binomial formula, and can also be understood in terms of k-combinations by taking the complement of such a combination, which is an (n − k)-combination.

Finally there is a formula which exhibits this symmetry directly, and has the merit of being easy to remember:

where n! denotes the factorial of n. It is obtained from the previous formula by multiplying denominator and numerator by (n − k)!, so it is certainly computationally less efficient than that formula.

The last formula can be understood directly, by considering the n! permutations of all the elements of S. Each such permutation gives a k-combination by selecting its first k elements. There are many duplicate selections: any combined permutation of the first k elements among each other, and of the final (n − k) elements among each other produces the same combination; this explains the division in the formula.

From the above formulas follow relations between adjacent numbers in Pascal’s triangle in all three directions:

Together with the basic cases , these allow successive computation of respectively all numbers of combinations from the same set (a row in Pascal’s triangle), of k-combinations of sets of growing sizes, and of combinations with a complement of fixed size n − k.

Example of counting combinations[edit]

As a specific example, one can compute the number of five-card hands possible from a standard fifty-two card deck as:^[7]

Alternatively one may use the formula in terms of factorials and cancel the factors in the numerator against parts of the factors in the denominator, after which only multiplication of the remaining factors is required:

Another alternative computation, equivalent to the first, is based on writing

which gives

When evaluated in the following order, 52 ÷ 1 × 51 ÷ 2 × 50 ÷ 3 × 49 ÷ 4 × 48 ÷ 5, this can be computed using only integer arithmetic. The reason is that when each division occurs, the intermediate result that is produced is itself a binomial coefficient, so no remainders ever occur.

Using the symmetric formula in terms of factorials without performing simplifications gives a rather extensive calculation:

Enumerating k-combinations[edit]

One can enumerate all k-combinations of a given set S of n elements in some fixed order, which establishes a bijection from an interval of integers with the set of those k-combinations. Assuming S is itself ordered, for instance S = { 1, 2, …, n }, there are two natural possibilities for ordering its k-combinations: by comparing their smallest elements first (as in the illustrations above) or by comparing their largest elements first. The latter option has the advantage that adding a new largest element to S will not change the initial part of the enumeration, but just add the new k-combinations of the larger set after the previous ones. Repeating this process, the enumeration can be extended indefinitely with k-combinations of ever larger sets. If moreover the intervals of the integers are taken to start at 0, then the k-combination at a given place i in the enumeration can be computed easily from i, and the bijection so obtained is known as the combinatorial number system. It is also known as «rank»/»ranking» and «unranking» in computational mathematics.^[8][9]

There are many ways to enumerate k combinations. One way is to visit all the binary numbers less than 2ⁿ. Choose those numbers having k nonzero bits, although this is very inefficient even for small n (e.g. n = 20 would require visiting about one million numbers while the maximum number of allowed k combinations is about 186 thousand for k = 10). The positions of these 1 bits in such a number is a specific k-combination of the set { 1, …, n }.^[10] Another simple, faster way is to track k index numbers of the elements selected, starting with {0 .. k−1} (zero-based) or {1 .. k} (one-based) as the first allowed k-combination and then repeatedly moving to the next allowed k-combination by incrementing the last index number if it is lower than n-1 (zero-based) or n (one-based) or the last index number x that is less than the index number following it minus one if such an index exists and resetting the index numbers after x to {x+1, x+2, …}.

Number of combinations with repetition[edit]

A k—combination with repetitions, or k—multicombination, or multisubset of size k from a set S of size n is given by a set of k not necessarily distinct elements of S, where order is not taken into account: two sequences define the same multiset if one can be obtained from the other by permuting the terms. In other words, it is a sample of k elements from a set of n elements allowing for duplicates (i.e., with replacement) but disregarding different orderings (e.g. {2,1,2} = {1,2,2}). Associate an index to each element of S and think of the elements of S as types of objects, then we can let denote the number of elements of type i in a multisubset. The number of multisubsets of size k is then the number of nonnegative integer (so allowing zero) solutions of the Diophantine equation:^[11]

If S has n elements, the number of such k-multisubsets is denoted by

a notation that is analogous to the binomial coefficient which counts k-subsets. This expression, n multichoose k,^[12] can also be given in terms of binomial coefficients:

This relationship can be easily proved using a representation known as stars and bars.^[13]

As with binomial coefficients, there are several relationships between these multichoose expressions. For example, for ,

This identity follows from interchanging the stars and bars in the above representation.^[15]

Example of counting multisubsets[edit]

For example, if you have four types of donuts (n = 4) on a menu to choose from and you want three donuts (k = 3), the number of ways to choose the donuts with repetition can be calculated as

This result can be verified by listing all the 3-multisubsets of the set S = {1,2,3,4}. This is displayed in the following table.^[16] The second column lists the donuts you actually chose, the third column shows the nonnegative integer solutions of the equation and the last column gives the stars and bars representation of the solutions.^[17]

No.	3-multiset	Eq. solution	Stars and bars
1	{1,1,1}	[3,0,0,0]
2	{1,1,2}	[2,1,0,0]
3	{1,1,3}	[2,0,1,0]
4	{1,1,4}	[2,0,0,1]
5	{1,2,2}	[1,2,0,0]
6	{1,2,3}	[1,1,1,0]
7	{1,2,4}	[1,1,0,1]
8	{1,3,3}	[1,0,2,0]
9	{1,3,4}	[1,0,1,1]
10	{1,4,4}	[1,0,0,2]
11	{2,2,2}	[0,3,0,0]
12	{2,2,3}	[0,2,1,0]
13	{2,2,4}	[0,2,0,1]
14	{2,3,3}	[0,1,2,0]
15	{2,3,4}	[0,1,1,1]
16	{2,4,4}	[0,1,0,2]
17	{3,3,3}	[0,0,3,0]
18	{3,3,4}	[0,0,2,1]
19	{3,4,4}	[0,0,1,2]
20	{4,4,4}	[0,0,0,3]

Number of k-combinations for all k[edit]

The number of k-combinations for all k is the number of subsets of a set of n elements. There are several ways to see that this number is 2ⁿ. In terms of combinations, , which is the sum of the nth row (counting from 0) of the binomial coefficients in Pascal’s triangle. These combinations (subsets) are enumerated by the 1 digits of the set of base 2 numbers counting from 0 to 2ⁿ − 1, where each digit position is an item from the set of n.

Given 3 cards numbered 1 to 3, there are 8 distinct combinations (subsets), including the empty set:

Representing these subsets (in the same order) as base 2 numerals:

• 0 – 000
• 1 – 001
• 2 – 010
• 3 – 011
• 4 – 100
• 5 – 101
• 6 – 110
• 7 – 111

Probability: sampling a random combination[edit]

There are various algorithms to pick out a random combination from a given set or list. Rejection sampling is extremely slow for large sample sizes. One way to select a k-combination efficiently from a population of size n is to iterate across each element of the population, and at each step pick that element with a dynamically changing probability of (see Reservoir sampling). Another is to pick a random non-negative integer less than and convert it into a combination using the combinatorial number system.

Number of ways to put objects into bins[edit]

A combination can also be thought of as a selection of two sets of items: those that go into the chosen bin and those that go into the unchosen bin. This can be generalized to any number of bins with the constraint that every item must go to exactly one bin. The number of ways to put objects into bins is given by the multinomial coefficient

where n is the number of items, m is the number of bins, and is the number of items that go into bin i.

One way to see why this equation holds is to first number the objects arbitrarily from 1 to n and put the objects with numbers into the first bin in order, the objects with numbers into the second bin in order, and so on. There are distinct numberings, but many of them are equivalent, because only the set of items in a bin matters, not their order in it. Every combined permutation of each bins’ contents produces an equivalent way of putting items into bins. As a result, every equivalence class consists of distinct numberings, and the number of equivalence classes is .

The binomial coefficient is the special case where k items go into the chosen bin and the remaining items go into the unchosen bin:

See also[edit]

Notes[edit]

References[edit]

• Benjamin, Arthur T.; Quinn, Jennifer J. (2003), Proofs that Really Count: The Art of Combinatorial Proof, The Dolciani Mathematical Expositions 27, The Mathematical Association of America, ISBN 978-0-88385-333-7
• Brualdi, Richard A. (2010), Introductory Combinatorics (5th ed.), Pearson Prentice Hall, ISBN 978-0-13-602040-0
• Erwin Kreyszig, Advanced Engineering Mathematics, John Wiley & Sons, INC, 1999.
• Mazur, David R. (2010), Combinatorics: A Guided Tour, Mathematical Association of America, ISBN 978-0-88385-762-5
• Ryser, Herbert John (1963), Combinatorial Mathematics, The Carus Mathematical Monographs 14, Mathematical Association of America

External links[edit]

• Topcoder tutorial on combinatorics
• C code to generate all combinations of n elements chosen as k
• Many Common types of permutation and combination math problems, with detailed solutions
• The Unknown Formula For combinations when choices can be repeated and order does not matter
• Combinations with repetitions (by: Akshatha AG and Smitha B)^{[permanent dead link]}
• The dice roll with a given sum problem An application of the combinations with repetition to rolling multiple dice

noun

COLLOCATIONS FROM OTHER ENTRIES

a colour combination/combination of colours (=the colours that exist or that you put together)

▪ In autumn the leaves create lovely colour combinations.

a colour combination/combination of colours (=the colours that exist or that you put together)

▪ In autumn the leaves create lovely colour combinations.

a combination/variety/number of factors

▪ A combination of factors led to the closure of the factory.

a lethal combination

▪ Higher taxes and higher inflation were a lethal combination.

a set/combination of circumstances

▪ This was a very unusual set of circumstances.

combination lock

combination oven

COLLOCATIONS FROM CORPUS

■ ADJECTIVE

different

▪ The system can be used in different combinations and packs down into one stuff sack.

▪ Abbott has not yet analyzed the results for patients taking different combinations of drugs.

▪ Taken together, different combinations of presidential, electoral, and party systems can have profound effects on democratic performance.

▪ Why are there different combinations of extinct species in each layer of rock?

▪ You end up with a gridded image with each square a different combination of negative exposure and flash exposure.

▪ He mixes different combinations and succeeds in getting the yellow color and then losing it.

▪ You will in fact find any shade will look acceptable so experiment with different combinations before embarking on an actual garment.

▪ It is a random arrangement of all the colors imaginable, with continually different color combinations at every glance.

lethal

▪ N New tank syndrome: A lethal combination of all the problems mentioned in this article.

▪ Not to mention that lethal combination of hands and strength.

▪ Together however, these factors can prove a lethal combination.

▪ This is a potentially lethal combination, but modern techniques help to safeguard us from those risks.

▪ The little church has suffered from the rigours of time and town planning, normally a lethal combination, and survived.

▪ An aptly named gas, discovered in 1766, it had that potentially lethal combination of having both explosive and lifting properties.

possible

▪ This distinction, coupled with the previous one, yields four possible combinations of fact, each needing discussion.

▪ The design of an experiment typically takes two of these factors and combines them in all possible combinations.

▪ Some people fondly believe that chess-playing computers work by internally trying out all possible combinations of chess moves.

▪ There are 25 possible combinations of two or more of the liquids.

▪ Now let us look at the possible combinations.

▪ As you can imagine, there are many possible combinations.

▪ The figure therefore gives the possible combinations of project outcome and additional information.

▪ The Census forms admit of some 63 possible combinations of race.

right

▪ Always practise on a sample of fabric first to find the right combination.

▪ The right combination of convictions could ship him to death row.

▪ It is sometimes difficult to fet the right combination of storage and hanging space.

▪ Picking the right combination for a team is one of the keys to a successful climb.

▪ Systematic Cleaning Systematic cleaning is the adoption of the right combination of energy for the circumstances with regard to time and cost.

▪ The makers Schott claim that this porous glass material has exactly the right combination of aerobic and anaerobic opportunities for bacterial growth.

unique

▪ From this superb range comes Ribbon Gel; a unique striped combination gel.

▪ They employed a unique combination of theoretic analysis, practical grasp, and imaginative foresight.

▪ Our unique combination of skills has helped literally thousands of companies.

▪ The scenery is breathtaking, a unique combination of mountains, fells, pastures and forested valleys filled with lakes and farms.

▪ A unique combination, offering an unequalled nationwide service.

▪ The membership of the teams is bringing together a unique combination of experience and expertise in developing services for carers.

▪ The Open University has a unique combination of foundation courses followed by a modular course structure.

▪ This may well be a unique combination which will produce a slightly different organism with new characteristics.

various

▪ The point is that various combinations of government and private sector organization, finance and production are possible.

▪ The manager is concerned about how teams are orchestrated on various scales, with various combinations of players and various resources exchanged.

▪ Other techniques may also be used, both in isolation and in various combinations.

▪ These are doubled up in various combinations to form up to 64 hexagrams.

▪ Yamaha use various combinations of polyester and polyurethane on their guitars.

▪ This approach is broadly statistical in nature, as it involves corpus analysis to determine the empirical likelihood of various syntactic combinations.

▪ The results of associating various combinations of thymocytes and stromal cells are summarized in Table 1.

▪ The remaining lines to the right have all been climbed by various combinations of Newton, McGinley and Liz Wade.

■ NOUN

drug

▪ Nineteen had used only one drug prior to heroin use, principally cannabis, the rest using a variety of drug combinations.

▪ At that point, they are put on other drug combinations.

lock

▪ He laid it on the bed, turned the combination locks and lifted the lid.

▪ I took it down from the wall to reveal the circular door of a wall safe with a combination lock.

▪ Next to it was a steel security cupboard fitted with a combination lock.

▪ The case sported matching brass hardware, including a pair of clasps, each with its own three-number combination lock.

▪ Remember the analogy of the combination lock.

▪ The only thing holding me up would be fumbling at the combination lock or renting a towel.

▪ And a briefcase with one of those combination locks.

▪ I had twenty minutes to see what I could do about his combination locks.

therapy

▪ But he says that any drugs to block this process would have to form part of a combination therapy.

▪ Kaiser says it will also provide the latest three-drug combination therapies, if appropriate.

▪ Data from combination therapy studies are also gradually becoming available.

▪ Thus, for several reasons, combination therapy with artemisinin or a derivative makes therapeutic sense.

▪ She said he had not shown any symptoms for some time but had recently started taking combination therapy drugs.

■ VERB

involve

▪ Training methods involve repeating these combinations until the juxtaposition of foot, hip and shoulder becomes automatic.

▪ The program involves a combination of relaxation and visualization exercises, along with some structured statements called affirmations.

▪ Her exercising and her diets, involving theories about food combinations, had irritated me for months.

▪ Frequently the stresses involve a combination of these different levels.

▪ Helping the Disabled Siting a new bureau involves a complex combination of local objectives, suitability, costing and availability.

▪ Human machines everywhere are built up from mechanisms involving combinations of motion in a straight line and motion in a circle.

▪ The approach to pro-active searches is well established and involves a combination of desk and field research.

offer

▪ The latest addition to our successful twin-colour Designer Range of Tilturn and Casement windows offers endless colour combinations, inside and out.

▪ Technology analysts offered a combination of answers last weekend.

▪ Powter offers women an irresistible combination of promises.

▪ The approach is cognitive and the books offer a combination of explanations, examples, and a variety of imaginative exercises.

▪ Prestige saucepans and bakeware offer the perfect combination — excellent performance and quality.

▪ Delapre Park offers a charming combination of an Elizabethan walled garden, parkland and woodland walks.

▪ A well-designed and efficiently controlled system offers the best combination of comfort, convenience and economy, but it’s not essential.

use

▪ Many complementary practitioners use combinations of these disciplines.

▪ We have arbitrarily grouped them in three categories: Many of these methods can be used in combination.

▪ Thrusters were then used to pull the combination further ahead.

▪ We shall only use these strange complex-number combinations at the quantum level.

▪ Different tribes often use different colours and combinations of feathers to identify themselves.

▪ Sometimes it is necessary to use a combination of two AEDs.

▪ She used a combination of small weights, to have the fun of adding them up.

▪ They are used in combination to set apart two main groups, the detrital and the chemical.

EXAMPLES FROM OTHER ENTRIES

▪ Banana, orange juice, and cream may seem an odd combination, but together they make a delicious drink.

▪ I’ll have the shrimp and chicken combination, please.

▪ If all the team are playing well, then don’t change a winning combination.

▪ Our problems were due to a combination of bad management and lack of experience.

▪ The new device is a combination copier, fax, image scanner, and document printer.

▪ The sweater is made of a combination of natural and synthetic fibres.

▪ Their music is an odd combination of jazz and opera.

▪ They were a perfect combination — Anton as chef and Guy as restaurant manager.

▪ What’s the matter? Can’t you remember the combination?

EXAMPLES FROM CORPUS

▪ A combination of fears leads to this unfortunate situation.

▪ He had tried every combination of the antibiotics we had on board, and was running out of tablets.

▪ His leadership style was to maintain power through a combination of force and cunning strategy.

▪ Most were attracted by her intoxicating combination of beauty, wit and charm, but others were cowed.

▪ The nationalization of local politics arose from a specific combination of economic, social and political processes which no longer applies.

▪ This combination of your political beliefs and actions is the essence of the domain of political science called political behavior or micropolitics.

▪ This, as far as we know, is the first reported case of the combination of gold induced and infective colitis.