Word formation prefixes with the meaning not

Word Formation

Prefixes

With the meaning ‘not’

• un is used with many different words
• im is used before some words begining with m or p, ex: impolite, impatient
• il is used before some words begining with l, ex: illegible
• ir is only used before some words beginning with r, ex: irresponsible
• dis is used before some adjectives, ex: dishonest, and a few verbs, ex: dislike, disagree
• in is used before a limited number of words, ex: invisible

Suffixes

Noun suffixes

Verb + suffix -> Noun

Verb	Suffix	Noun
improve	-ment	improvement
manage	-ment	management
elect	-ion	election
discuss	-ion	discussion
inform	-ation	information
organise	-ation	organisation
jog	-ing	jogging
spell	-ing	spelling

Note: Sometimes there is a spelling change. The most common is the omission of the final ‘e’ befor the suffix -ion or -ation: translate/translation; organise/organisation

Adjective + suffix -> Noun

Adjective	Suffix	Noun
weak	-ness	weakness
happy	-ness	happiness
dark	-ness	darkness
stupid	-ity	stupidity
punctual	-ity	puncuality
similar	-ity	similarity

Adjective suffixes

Noun or verb + suffix -> Adjective

Noun or Verb	Suffix	Adjective
danger, fame	-ous	dangerous, famous
music, politics, industry, economics	-al	musical, political, industrial, economical
cloud, fog, sun, dirt	-y	cloudy, foggy, sunny, dirty
attract, create	-ive	attractive, creative
knowledge, drink, comprehend, flex, eat	-able, -ible	knowledgeable, (un)drinkable, (in)comprehensible, (in)flexible, (in)edible
use, thought, pain	-ful, -less	useful, useless, thoughtful, thoughtless, painful, painless

Note: Sometimes there is a spelling change. Here are common examples:

• double the consonant, ex: sun/sunny, fog/foggy
• leave out the final ‘e’, ex: create/creative, fame/famous
• leave out the final ‘s’ before ‘al’, ex: politics/political, economics/economical
• change ‘y’ to ‘i’ before ‘al’, ex: industry/industrial

Theory:

Prefixes and Suffixes are used to generate words of the same family as the source word.

Happy gives Unhappy by the addition of UN, and both words are part of the same family.

There is a group of prefixes which are used to create the opposite of a word.

These are UN, IM, IN, IL, IR and DIS.

For example,

happy — UN happy

visible — IN visible

legible — IL legible

possible — IM possible

responsible — IR responsible

honest — DIS honest

It is important to note that the addition of suffixes often change the spelling but the addition of prefixes do not affect the spelling of the word. They can sometimes affect the way the word is pronounced.

Often the prefixes UN and DIS are used to create the opposite form of adjectives,

happy — UN happy

honest — DIS honest

but they can also be used with verbs to create other verbs with the reverse action.

lock — UN lock

appear — DIS appear

There are some other prefixes that have specific meanings when used with verbs,

RE, OVER, and MIS,

write — RE write (RE here means DO AGAIN.)

cook — OVER cook (OVER here means TOO MUCH.)

understand — MIS understand (MIS here means incorrectly.)

Тест недоступен для мобильных устройств.

В английском языке есть ряд отрицательных приставок – negative prefixes. Сегодня поговорим о них. После прохождения теории обязательно выполните упражнения на отрицательные приставки (negative prefixes exercises) для того, чтобы лучше усвоить материал.

Наиболее часто в английском языке употребляются отрицательные приставки:

in- , un- , im- , il- , ir- , non- , de- , dis- , mis- , a- , anti-

Плохая новость состоит в том, что употребление приставок, как и другие моменты словообразования в английском языке, плохо поддается толкованию правилами, а потому в основном Вам придется надеяться на свою память и усидчивость. Все же есть некоторые правила, изобилующие исключениями, и относительно отрицательных приставок.

Приступим и будем планомерно изучать negative suffixes для разных частей речи.

Отрицательные приставки английских прилагательных.

Приставка	Значение и употребление	Примеры.
Un-	Отрицательная приставка. С ее помощью образуется основная масса отрицательных прилагательных.	unable — неспособный, unaware — неосведомленный, uncertain — неуверенный, unclear — неясный, unfriendly — недружелюбный, unhelpful — бесполезный, uninformed -неосведомленный, unknown — неизвестный, unpleasant — неприятный, unpredictable – непредсказуемый
In-	Приставка с отрицательным значением, которая в основном употребляется перед  ac / c	Inaccessible — недостижимый, Inaccurate — неточный, Inadequate — неадекватный, Incapable — неспособный, Incomplete — незавершенный, Incredible – невероятный. Исключения: indefinite, inevitable, infinite, inflexible, informal, insecure, insignificant, invalid, invariable, invisible, involuntary.
Il-	Употребляется только перед l.	Illegal — нелегальный, Illegible – нечеткий, неразборчивый, Illiterate — неграмотный, Illogical – нелогичный Исключение: disloyal
Ir-	Употребляется только перед r.	Irrational — нерациональный, Irregular — неправильный, Irrelevant — неуместный, Irreparable — неисправимый, Irresistible — неотразимый, Irresponsible — безответственный, Irreversible – необратимый.
Im-	Употребляется перед p, реже перед m.	Immature — незрелый, Impatient — неспокойный, Imperfect — неидеальный, Impossible — невозможный, Imprecise – неточный.
Dis-	Случаи употребления dis- необходимо запомнить	Disagreeable – неприятный, Dishonorable – позорный, Dishonest — бесчестный, Disloyal – нелояльный; Distasteful – противный, distrustful  — недоверчивый.
Non-	Случаи употребления non- необходимо запомнить	Nonexistent — несуществующий, Nonmetallic – неметаллический, Nonpartisan — беспартийный, Nonresident – не проживающий здесь.

 Обратите внимание на написание слов с приставкой non- . Большинство из ниx имеет двоякое написание (с дефисом и без):

Non-existent или nonexistent.

Однако некоторые пишутся только без дефиса – как, например, nonmetallic. Именно поэтому я все же склоняюсь к написанию без дефиса во всех случаях, чтобы избежать ненужных ошибок.

Отрицательные приставки английских глаголов.

Приставка	Значение и употребление	Примеры.
Un-	Очень редко употребляется вместе с глаголами. Имеет значение “удалить”	Unscheduled – удалить из расписания Unfriend – удалить из друзей
De-	Отрицательная приставка, которая часто остается и в русском языке (де-) или переводится как “раз-”.	Deactivate — деактивировать, Decode — декодировать, Decommission — списывать, Decompose — разбирать, Deconstruct –разбирать, Decontaminate — дезинфицировать, Decrease — уменьшать, Deform — деформировать, Derail – сходить с рельсов.
Dis-	Отрицательная приставка, часто переводится как “не” или “дез”.	Disagree – не соглашаться, Disfigure – обезображивать, Disinfect – дезинфицировать, Disinherit – лишать наследства, Disintegrate – дезинтегрировать, displease  — не нравиться, distrust – не доверять.
Mis-	Имеет значение “неправильно”.	Misdiagnose — поставить неверный диагноз, Misinform — неправильно информировать, Misinterpret — неверно истолковывать, Mislead — вводить в заблуждение, Misplace — поставить не на то место, Misspell — делать орфографические ошибки, Mistake – ошибаться, Misunderstand — неправильно понять.

Отрицательные приставки английских существительных.

De-

Отрицательную приставку de имеют существительные, образованные от глаголов с de-:

deflation, decomposition, deactivation, decontamination

Dis-

Приставку dis имеют существительные, образованные от глаголов или прилагательных с приставкой dis.

Disability, disagreement, disbelief, disinfection, disintegration, disloyalty, displeasure, distaste, distrust

In- ( il- , im- , ir-)

Эти приставки имеют существительные, образованные от соответствующих прилагательных.

illiteracy, immaturity, imperfection, impossibility, inaccessibility, inaccuracy, inappropriateness, incapability, incompatibility, inconsistency, infinity, inflexibility, insecurity, insufficiency, invalidity,  invisibility, irrationality, irregularity, irresponsibility. 

Mis-

Отрицательную приставку mis имеют существительные, образованные от глаголов с данной приставкой:

Misconduct, misdiagnosis, misinformation, misinterpretation, misspelling, mistake, mistrust, misunderstanding

Non-

Отрицательная приставка non характерна для единичных существительных:

nonconformist / nonconformity, nonexistence, nonintervention, nonsense

Un-

Отрицательную приставку un имеют существительные, образованные от прилагательных с приставкой un:

unawareness, uncertainty, unpleasantness, unpredictability

Отрицательные приставки – упражнения.

Давайте немного попрактикуемся в употреблении отрицательных приставок.

Упражнение 1. Сформируйте отрицательные существительные при помощи приставок un- , in- , dis- , mis- , de-

1. Honesty,
2. Certainty,
3. Security,
4. Dependence,
5. Importance,
6. Employment,
7. Connection,
8. Activation,
9. Belief,
10. Ability

Упражнение 2. Допишите отрицательные приставки следующим прилагательным.

1. an __friendly look
2. an __interesting book
3. an __natural colour
4. an __important task
5. an __possible answer
6. an __personal letter
7. an __definite article
8. an __correct answer
9. __direct speech
10. an __regular verb
11. an __responsible person

Упражнение 3. Сформируйте отрицательные прилагательные, используя приставки un- или in-

Happy, lucky, attentive, capable, comfortable, known, dependent, clean, necessary, pleasant, expensive, human, popular, expressive, definite, real, countable, direct, convenient, accurate

Упражнение 4. Замените фразы одним словом

Example: not countable — uncountable

1. Not necessary –
2. Not safe —
3. Not tidy—
4. Not breakable —
5. Not regular —
6. Not real —
7. Not expensive —
8. Not happy —
9. Not possible —
10. Not usual—
11. Not comfortable —
12. Not direct —
13. Not interesting —
14. Not patient —
15. Not convenient —
16. Not popular —

Упражнение 5. Заполните таблицу по образцу.

Прилагательное	Отрицательное прилагательное	Синоним
Friendly	Unfriendly	hostile

Прилагательные: useful, doubtful, expensive, correct, clean, interesting, natural, healthy, important, polite.

artificial, rude, dirty, cheap, wrong, boring, sick, insignificant

Упражнение 6.

Choose the correct prefix to make negative forms of the adjectives.

1) He was short and overweight and generally fairly __attractive. 

1. a) dis-; b) im-; c) in-; d) un- .

2) He’s a good teacher, but tends to be a bit __patient with slow learners.

1. a) un-; b) in-; c) im-; d) dis- .

3) It is an __logical statement, because if one part is true, then the other must be false.

1. a) dis-; b) il-; c) in-; d) un- .

4) It is __ polite to point at people.

1. a) dis-; b) im-; c) in-; d) un- .

5) My friend is very  __responsible, he never does anything in time.

1. a) dis-; b) ir-; c) in-; d) un- .

6) He’s very __patient. He can’t work as a teacher.

1. a) dis-; b) im-; c) in-;    d) un- .

7) He’s an __forgiving person. He never forgives people.

1. a) dis-; b) ir-; c) in-;    d) un- .

Ответы:

Exercise 1.

1. Dishonesty,
2. Uncertainty,
3. Insecurity,
4. Independence,
5. Unimportance,
6. Unemployment
7. Disconnection,
8. Deactivation,
9. Disbelief,

Exercise 2.

1. an unfriendly look
2. an uninteresting book
3. an unnatural colour
4. an unimportant task
5. an impossible answer
6. an impersonal letter
7. an indefinite article
8. an incorrect answer
9. indirect speech
10. an irregular verb
11. an irresponsible person

Exercise 3.

UN + Happy, lucky, comfortable, known, clean, necessary, pleasant, popular, real, countable

IN + Attentive, capable, dependent, expensive, human, expressive, definite, direct, convenient, accurate

Exercise 4.

1 unnecessary, 2 unsafe, 3 untidy, 4 unbreakable, 5 irregular, 6 unreal, 7 inexpensive, 8 unhappy, 9 impossible, 10 unusual, 11 uncomfortable, 12 indirect, 13 uninteresting, 14 impatient, 15 inconvenient, 16 unpopular

Exercise 5.

Прилагательное	Отрицательное прилагательное	Синоним
Friendly Expensive Correct Clean Interesting Natural Healthy Important Polite	Unfriendly Inexpensive Incorrect Unclean Uninteresting Unnatural Unhealthy Unimportant Impolite	Hostile Cheap Wrong Dirty Boring Artificial Sick Insignificant Rude

Exercise 6.

1 d, 2 c, 3 b, 4 b, 5 b, 6 b, 7 d

Надеюсь, употребление отрицательных приставок в английском языке не стало для Вас сложной темой.

Понравилось? Сохраните на будущее и поделитесь с друзьями!

Ricardo: “I can say ‘The price is uncorrect?’”
Me: “No, the right word is incorrect.”
Ricardo: “Why?”
Me: “Great question.”
Enter this post.

The English language provides us with several ways to negate words, one of which is the use of negative affixes (i.e. prefixes and suffixes). In other words, a letter or group of letters can be attached to the beginning (prefix) or end (suffix) of a word to change its meaning. Although prefixes and suffixes can be used in a variety of scenarios to modify the meaning of a root word, this post will address their use as a method for negating words. Take for example the above interaction. In order to obtain the opposite/negative/contrary meaning of the word correct, we had to add the prefix in-, resulting in the word incorrect.

But how do we know the word is incorrect, not uncorrect? Unstable, not instable? Irregular, not unregular?

Both in- and un- convey the meaning of “not something,” which can lead to confusion regarding which (if any) prefixes to use. This post will start by describing the different prefixes (10 in total!) and one suffix that can be used to negate a word. The next section will address some exceptions and other interesting comments. Finally, I will complete a brief comparative analysis of the use of negative affixes in other languages.

NEGATIVE PREFIXES AND SUFFIX

Prefixes can be classified either based on the role they play/effect they have (semantically) or by the type of grammar rules applicable to them (grammatically). I have chosen to divide the prefixes semantically, which gives us the following categories: negative prefixes (a(n), dis-, in-, non-, un-), reversative or privative prefixes (de-, dis-, un-), pejorative prefixes (mal-, mis-) and prefixes of opposition (anti-, counter-).

Source: prepared using data from Merriam Webster’s online dictionary.
*Exceptions discussed in further detail below.

The question is, with so many options, how do native speakers and learners of English know which prefix to use? Unfortunately, there are few rules in this regard and those that do exist are based on the origin of the root word (Germanic, Greek or Latin) which, I imagine, most people and, in particular, nonnative speakers, will not know.

Negative Prefixes

This first category comprises the “true” negative prefixes. I say true, because oftentimes the term negative prefixes is used to refer to all 10 of the above prefixes, but only more accurately applies to 5 of them. What is a negative prefix? Negative prefixes are those that have the meaning of “not ____” or “lacking of,” which includes the following prefixes: a-, dis, in-, non- and un-.

A(N)-

This prefix has its roots in the Greek prefix “a-,” which means “without” or “lack of.”

When is this prefix used? And, again, bear in mind that these are not strict rules, but rather just a few useful observations.

1. Often used with adjectives formed from nouns: (color – (a)chromatic ; symmetry – (a)symmetric)
2. Adjectives ending in –al (e.g. amoral, asexual, atypical, asymmetrical)
3. Words of Greek origin (dictionary.com is a good place t0 check word origin)
4. Technical or scientific words (e.g. atrophy, anarchism, anorexia, asymmetry)
5. Not usually used with verbs or adverbs

One final note. Although this prefix is generally used before words starting with a consonant, when it does precede a word starting with a vowel, the prefix becomes an–.

DIS-

This prefix has several meanings and can be used with verbs, adjectives, nouns and adverbs! As with all the other prefixes in this category, this prefix can mean “not ______” or “lacking of.” However, as we will see in the section on reversative/privative prefixes, it can also mean “opposite of.”

As the origin of the prefix comes from Latin, this word is often used with words of Latin origin. (e.g. disloyal, dishonest, discomfort).

IN-

The most common problem or confusion with this prefix can be summarized by the following question; “What is the difference between im, in, il, and ir?” Essentially nothing. In- is the basic prefix; however, it is subject to modification based on the first letter of the main word it is modifying, in order to ease pronunciation. For those of you that are familiar with Spanish, this is similar to use of the word “e” to mean “and,” instead of the normal “y,” when it is followed by a word starting with the “EEE” sound (e.g. las mujeres e hijas). In English, the prefix in- changes according to the following rules:

• im– before words beginning with m or p (e.g. immaterial, impertinent, imperfect)
• il– before words beginning with l (e.g. illegal, illegitimate, illegible)
• ir– before words beginning with r (e.g. irrelevant, irrational, irrelevant)

The prefix in- can also be modified to ig–, although this is not very common. The only words I can think of are ignoble and ignominious, and none of these words are used very frequently.

As mentioned above, this prefix means “not _____.” However, it is important to note that this prefix may also sometimes be used to add emphasis to/intensify a word. This is the case with the words invaluable, illuminate, innovative, incredible, and inflammable.

A common complaint of English learners, and what triggered this post, is the difference between in- and un-. These two prefixes are the most commonly confused. On a very basic level, the distinction here is that in- comes from Latin and is therefore used primarily with words of Latin origin, whereas words of Germanic origin tend to take the prefix un- (Fowler). However, it’s not quite as simple as it sounds.

As with many aspects of English grammar, there is much inconsistency in the use of these prefixes. Over the course of history, this inconsistency has been primarily driven by the availability of a foreign (in-) and a native (un-) prefix, both with the same meaning. As the English language was developing, it faced a choice between directly adopting foreign words (in-) or translating those words into English by changing the prefix to un-.

This inconsistency was all but nonexistent in Old English; however, this problem of which prefix to use grew alongside the growing English language. This can most likely be attributed to the increased borrowing of Latin-origin words through French, thanks to the Norman invasion of the British Isles, which was then codified in dictionaries. The problem with this is that the lexicographers were making choices between codifying words with in– or un- primarily based on personal preference, not following any sort of semantic or grammatical rules (Seale 1).

NON-

This prefix is one of the two prefixes (together with ANTI-) that is most frequently used to create new words in the English language.

In general, this prefix is attached to adjectives and slightly less frequently to nouns, but almost never to adverbs or verbs. Examples of use with an adjective include: noncompliant, nonessential, nonpartisan and non-dairy[1]. Examples of use with nouns include: nonconformist and noncompliance.

UN-

This is the most commonly used prefix to negate words to obtain the meaning “not + word.” So, when in doubt, use un-. It is interesting to note that this was not always the case, but un- is currently the preferred prefix as between in- and un-.

This prefix also has an additional meaning, which will be addressed under the section on reversative and privative prefixes.

Reversative and Privative Prefixes

These prefixes, together with the remaining prefixes discussed below, are not technically negative prefixes in the strict sense, but still convey the idea that we are straying from the meaning of the main word and heading into antonym-ish world.

Let me first start by breaking down what the heck “reversative” and “privative” mean. Reversative prefixes refer to the reversal of something and privative prefixes are used to convey the idea of “lacking.”

DIS-

When used with a verb, or with an adjective or adverb derived from the verb, it generally means the “opposite of.” (e.g. disenchanted, disagree, disprove).

UN-

When this prefix is used to modify a verb, un- means “to undo or reverse the action.” For example, untie, unfasten, unbuckle, etc. You may have noticed in the table above that there is another prefix (de-) that can be used to mean reversal of an action.

DE-

This prefix can also, similar to un-, be used to reverse the action of the verb being modified, although de- is much more commonly used for this purpose. Examples: defriend, deregulate, defrost. It is important to note that this prefix is generally only used when implying the reversal of an action that has in fact been taken. For example, dis- is used with the verb “member” to form dismember, as in to cut a body into pieces (sorry, kind of a grotesque example, but it was the best I could come up with). In this case, we could not use the prefix de-, as the action of first “membering” the body was never taken….the person just came pre-membered.

-LESS

The only suffix of this type, making its application and use very easy. It is used to express the idea that something does not have the quality of the base word. For example, odorless, meaningless, speechless.

Pejorative Prefixes

Pejorative prefixes are prefixes that provide a negative evaluation of the word being modified.

MAL- (badly) and MIS- (wrongly)

Mal- and Mis- are probably two of the easiest prefixes to apply. The former means badly and the latter wrongly. Although “bad” and “wrong” may at first glance appear tobe one and the same, there are slight differences. For example, you may heat a whole gallon of ice cream in one sitting. Is this bad, as in unhealthy, not good for you? Yes. Is it wrong? Probably only if someone forbade you to eat it and you did so anyway.

Examples with “mal-“: malnourished, malodorous, maladjusted
Examples with “mis-“: misadvise, misconduct, misdiagnose

Opposition Prefixes

Opposition prefixes are those that can be added to a word to convey the idea of opposite, opposed or against.

ANTI-

This one is relatively simple to use and also very helpful. It is used in three separate contexts:

1. “opposed to”                       Examples: anti-Semitism

1. “opposite”                           Examples: antithesis, antisocial

1. “acting to prevent sth.”  Examples: antibodies, antiaging, antifreeze, anti-inflammatory

COUNTER-

This prefix means the opposite of something. Consider counterclockwise, the opposite of clockwise. Examples: counterintuitive, counterfire, counterclaim, counterterrorism, and counterstrike (yes, as in the videogame).

SPECIAL CASES, EXCEPTIONS AND FINAL COMMENTS

Prefix Look-Alikes

I would also like to point out that not all words that appear to have a negative prefix actually do. There are many words that start with the same letters as these prefixes, that is, with these combinations of letters, but which are not always intended to negate something. This is the case in particular with verbs beginning with “in-.” Examples: incline, inform, and involve. The key here is to focus on the word following the introductory letters. If the main word (the one after the prefix or letters matching the prefix) is not a word on its own, then no prefix is at play (e.g. in the word in·cline, cline is not a word). Other examples of words that appear at first glance to be employing a prefix, but are not, are: alike, antiquated, decrease, destroy, include, illuminate, important, impact, irrigate, and universe.

Hyphens

As you probably noticed if you haven’t been bored to death reading this and actually made it to this point, words formed with these prefixes are sometimes joined using a hyphen (e.g. anti-American). So, when do we need to use a hyphen?

1. Depending on the personal preference of the writer, when there is a double vowel or double consonant (e.g. non-native, anti-inflammatory). Exception: hyphens are never used with the prefix in- (illegal)
2. Base word is a proper name/capitalized word (anti-American, sub-Saharan, un-English)
3. Before numbers (post-9/11)
4. With nouns formed using more than one prefix (non-self-governing)
5. Separating repeated double prefixes (sub-subsection)
6. If the prefix can stand alone as its own word (over-, under-, macro-, micro-, ex-, self-) Note: this does not apply to any of the prefixes addressed herein

Inconsistent Prefixes

Anyone thinking; “Cool, all I have to do is remember that stable goes with un-, and I can apply this to all of the forms of the word…adjectives, adverbs, nouns, verbs…everything!” Sorry, but no. The prefix used for one word type (e.g. adjective) is not always consistently used with the other variations of that same word. For example, the adjective able is negated using un- (unable), but its corresponding noun and verb forms are, respectively, inability and to disable. Some other examples include:

Luckily, this is the exception, and most words seem to maintain the same prefix across the different word forms. I was unable to find a specific rule (if there is one), on when words take the same prefixes and when not. Any knowledge/input on this topic would be awesome!

Multiple Prefixes per Word

Another note. A lot of words will accept numerous prefixes, but it is important to understand that this does not mean they are interchangeable. The choice of prefix will, in some cases, change the meaning of the word.

This first group of words that can take more than one suffix poses minimal problems for language learners, as the different prefixes the word accepts have different meanings.

Misdiagnosed: diagnosed improperly
Undiagnosed: not diagnosed at all, no diagnosis was provided

Misinformed: to be inaccurately apprised of something
Uninformed: to not be apprised of

Inappropriate: not suitable
Misappropriate: to take something dishonestly for your own use

This next grouping includes words that take more than one prefix where the meaning is more similar. In these cases, the words are primarily seen as synonyms, usually with use being a matter of preference. It is also interesting to note that many of these word combinations are not actually words. I have marked those words that do not technically appear in the dictionary, but which are oftentimes used by native speakers. As far as the difference between each variation, I have opted not to include a definition for those pairs of words that I felt were synonyms. I would love to hear your input though on any subtle differences you may see between each pair of words.

Unaffected: not influenced
Disaffected: disconnected

Unmoral: not affected or guided by morals
Amoral: having or showing no regard for morality, often relating to behavior

Unbelief: lack of belief
Disbelief: feeling of not being able to believe something

Disinterested: having no personal feelings or interest in something
Uninterested: not interested

Inability: lack of ability
Disability: condition that limits person’s physical or mental abilities

Irreligious: not believing in or practicing any religion
Unreligious: having no connection to religion
Antireligious: against or opposed to religion
Nonreligious: having nothing to do with religion

Unapproved: approval was rejected, not approved
Disapproved: not agreeing with or approving something

Dislike: to not like
Unlike: not similar

Unprofessional: conduct deviating from normal professional standards
Nonprofessional: describing someone that is not a professional in a particular field

Disorganized and Unorganized

Insecure and Unsecure*[2]

Infertile and Unfertile [3] 

Inept: lacking skill or ability
Inapt: not appropriate/suitable
Unapt: not likely

Incapable and Uncapable

No Prefix

Last but not least, words can be negated through the use of the word “not” as opposed to by prefixation. Unfortunately, there is, as far as I was able to discern, no clear line of when to use a prefix and when to use a separate word (i.e. not) for the purposes of negation. This is another here where I had trouble discerning any rules so, again, if anyone has any thoughts/knowledge I’d love to hear from you!

Unintelligent – not intelligent
To defund (take away funding) – not funded (didn’t receive funding)
Impossible – not possible
Disagree – not agree
Completely unfazed – not fazed at all
Unreliable – not reliable

Non-words

Last but not least, to emphasize the utter confusion in this area, I want to address words that native English speakers often have trouble with and ultimately opt for the wrong prefix. Common words that people use but which are not actually listed in most dictionaries include incertain and irregardless.

Let’s look a little more at irregardless, an interesting case of language evolution. The base word here, regardless, meaning lacking attention. At some point, people started using irregardless as its synonym (potentially as a combination of irrespective and regardless). So many people started using this word, that it is now in fact a word, although its use is still frowned upon.

COMPARATIVE STUDY

The following is a very brief look at how other languages handle this same issue. Many words in the other romance languages take the same/similar prefixes. For example, insufficient in English uses the same prefix in Spanish (insuficiente), Portuguese (insuficiente) and French (insuffisant). Although the prefix selected in German for this same word is un- (ungenügend), insuffizient can be used in more specialized language.

Comparative with Spanish

Spanish has a similar system of negating words using affixes, many of which are the same as in English. Spanish prefixes include A-, ANTI-, CONTRA-, DES-, IN-, MAL-. The prefix in- even changes based on the following letter, just as in English (e.g. irreparable, irrespectivo). Another interesting similarity is the tendency of natives to misuse irregardless (irrespectivo). And, yet another similarity here is that in- can also be used for emphasis, as in invaluable (incalculable).

Despite these similarities, it is important to remember that “un-” is a uniquely Germanic prefix and therefore, when translating such words from English into Spanish, the prefix will have to be adjusted. It would be great if there were a rule along the lines of “translate the un- prefix in English to in- in Spanish.” Unfortunately, this does not work 100% of the time, although by looking at the table below you can see that this rule can, in general, be applied.

Comparative with French

The available prefixes in French include A-, CONTRE-, DÉ(S)-, IN-, NON-, MAL-, and MÉ(S)-. You will notice the same thing as with Spanish, which is the lack of the un- prefix.

And here is a table comparing certain prefixed words in French and English:

I am not even going to try to come up with some sort of rule for when what word takes what prefix in which language.

Comparative with German

I wanted to add a section on German to see how these work with another Germanic language besides English. The available affixes here include the prefixes A-, DES, IN-, MISS-, VER- and UN- and the suffix –LOS, –FREI, and -LEER.

Some interesting things are happening here. First, let’s take a look at the prefix VER-. We do not have this prefix in English, but it is an extremely useful prefix in German that is essentially used to form the opposite of the root verb. For example, kaufen (to buy) becomes verkaufen (to sell).

As with English, there are certain words that may appear to be employing a prefix, but which are not. For example, the word Unmenge (a gazillion) is clearly not trying to negate the meaning of the root word “Menge,” which means amount or quantity.

As with the French, there appears on the surface to be no rhyme or reason to when to use which prefix.

CONCLUSION

That’s all folks. Sorry it was so long! Every time I tried to find an answer to a question I had, I discovered a bazillion new things I wanted to discuss. For those of you who are reading this as an English learner, I’m afraid to say that the best way to learn these really is by rote memorization. My suggestion would be to keep a piece of paper or page in a notebook with ten columns (one for each affix), and jot down words as you come across them!

Footnotes: 

[1] You may be wondering why there is a hyphen here. I will address the use of hyphens with prefixes at the end of this post.

[2] Follow this https://books.google.com/ngrams/interactive_chart?content=insecure%2Cunsecure&year_start=1900&year_end=2016&corpus=15&smoothing=3&share=&direct_url=t1%3B%2Cinsecure%3B%2Cc0%3B.t1%3B%2Cunsecure%3B%2Cc0“>link for a view of the Google Ngram for these two words.

[3] Follow this https://books.google.com/ngrams/interactive_chart?content=infertile%2C+unfertile&year_start=1900&year_end=2008&corpus=15&smoothing=3&share=&direct_url=t1%3B%2Cinfertile%3B%2Cc0%3B.t1%3B%2Cunfertile%3B%2Cc0“>link for a view of the Google Ngram for these two words.

Works Cited:

H.W. Fowler, A Dictionary of Modern English Usage: The Classic First Edition

Lea L. Seale, The Rise and Decline of Negative Doublets in English, American Speech, Vol. 35, No. 3 (Oct., 1960).