In traditional grammar, a contraction is the formation of a new word from one or more individual words. This often is a result of a common sequence of words, or, as in French, to maintain a flowing sound. However, contraction has gained a broader meaning both in linguistics and other areas of language research. Based on the latest definitions, contraction is shortening of a word, syllable, or word group by omission of internal letters. [ISO 4:1984]

In English, contractions are commonly used in speech and informal writing. They are almost always either negations with not or combinations of pronouns with auxiliary verbs, and in these cases always include an apostrophe in the written form.

The first category of contractions is those formed by an auxiliary verb or form of be plus the word not, with the o replaced by an apostrophe, e.g. don't, can't, wouldn't, haven't. Notable exceptions include won't, shan't and ain't.

Although these were historically contractions, there are good reasons in current English to analyze them as inflectional suffixes rather than contractions.^[1]

The second category is generally in the form of a pronoun (or occasionally a noun) plus an auxiliary verb or a form of to be, with the apostrophe replacing as few as one letter, as in it's for it is, or four letters, as in I'd for I would. One of the largest such contractions is I'd've for I would have. Auxiliary verbs which can be contracted include will, would, shall, have/has, and had. In British English it is acceptable to form a contraction with the verb have even when it is used as the primary verb (as with the phrase "I've a date today").

The only commonly used English contraction of two words that does not fall into any of the above categories is "let's", a contraction of "let us" that is used in forming the imperative mood in the first-person plural (e.g. "Let's go [somewhere]"). Use of the uncontracted "let us" typically carries an entirely different meaning (e.g. "Let us go [free]"). "Let us" is rarely seen in the former sense and "let's" is never seen in the latter one.

Although uncommon in written English, people often use complex contractions such as wouldn't've for would not have, or combining auxiliary verbs with nouns, e.g. John'd fix your TV if you asked him. Although these can look awkward in print, they are natural and frequently heard colloquialisms. Contractions in English are not mandatory as in some other languages. It is always acceptable to write out (or say) all of the words of a contraction, though native speakers of English may find a person not using contractions to sound overly formal.

Other single-word contractions include: ma'am for madam and fo'c'sle for forecastle.

Words like gov't for government and int'l for international are abbreviations, not to be confused with contractions.

Many people writing English confuse the possessive form of the pronoun it with its contractions. The possessive form has no apostrophe (its), while the contraction of it is or it has does have an apostrophe (it's). See List of frequently misused English words.

Outside the English contractions described above, contractions are virtually the same concept as portmanteaux.

Contractions are used sparingly in formal written English. The APA style Guide indicates that Contractions, including Latin abbreviations, are not used in plain text. The equivalent phrase in English must be written out. An exception to this is the Latin abbreviation et al. which may be used with citations outside of parentheses.^[2]

The French language has contractions to facilitate ease of speech, similar to English, as in C'est la vie ("That's life"), where c'est stands for ce+est ("that is"). In general, any monosyllabic word-final, non-silent e will contract if the following word begins with a vowel. For example the common words que (qu'-), je (j'-), and de (d'-). Unlike in English, however, these contractions are mandatory: one would never say (or write) *ce est or *que elle. Certain prepositions can also be merged with masculine and plural direct articles, such as au for à le, aux for à les, du for de le, and des for de les. As with other contractions, these are mandatory.

In Italian, prepositions merge with direct articles in predictable ways. The prepositions a, da, di, in, su, con and per combine with the various forms of the direct article, namely il, lo, la, l', i, gli, gl', and le.

• Contractions with a, da, di, in, and su are mandatory, but those with con and per are optional.
• Words in parentheses are no longer commonly used, but some still exist in common expressions such as colla voce.
• Formerly, gl' was used before words beginning with i, however it is no longer in common use.

The words ce and è (form of essere, to be) is contracted into c'è, there is.

• C'è un problema - There is a problem

Spanish Spanish has two mandatory phonetic contractions: al (to the) for a el, and del (of the) for de el (not to be confused with a él, meaning to him, and de él, meaning his or, more literally, of him).

In informal spoken registers of Spanish, the word para "for" can be contracted to pa, for example in the subordinating conjunction pa'que (from para que "in order that"): Pa'que te enteres.

In Portuguese, contractions are common. Several prepositions regularly contract with certain articles and pronouns. For instance, de (of) and por (by; formerly per) combine with the definite articles o and a (masculine and feminine forms of "the"), producing do, da (of the), pelo, pela (by the). The preposition de contracts with the pronouns ele and ela (he, she), producing dele, dela (his, her). In addition, some verb forms contract with enclitic object pronouns: e.g., the verb amar (to love) combines with the pronoun a (her), giving amá-la (to love her). See a list at Wikipedia in Portuguese: List of contracted prepositions.

In German prepositional phrases, one can often merge the preposition and the article; for example, von dem becomes vom, zu dem becomes zum, or an das becomes ans. Some of these are so common that they are mandatory. In informal speech, also aufm for auf dem, unterm for unter dem, etc. are used, but would be considered incorrect if written, except maybe in quoted direct speech, in appropriate context and style.

Regional dialects of German, and various local languages which usually were already used long before today's Standard German was built, use contractions usually more frequently than German, but varying widely between different local languages. The informally spoken German contractions are observed almost everywhere, most often, accompanied by additional ones, such as in den becoming in'n (sometimes im) or haben wir becoming hamwer, hammor, hemmer, or hamma depending on local intonation preferences. Bavarian features several contractions like e.g. gesund sind wir becoming xund samma which are schematically applied to all word or combinations of similar sound. Features like that are found in all central and southern language regions. A sample from Berlin: Sagen [Sie] einmal, Meister, kann man hier einmal hinein? is spoken as Samma, Meesta, kamma hier ma rin?

Several local languages along the Rhine have, possibly under influx of French, build contraction patterns involving up to entire sentences. In speech, words are often concatenated, frequently liaison is used. So, [Dat] kriegst Du nicht may become Kressenit, or Lohß mer jonn, han ich jesaat becomes Lomejon haschjesaat.

Mostly, there are no binding orthographies for local languages and dialects of German, so writing is left to a great extent to authors and their publishers. Outside quotations, at least, they usually pay little attention to print more than the most commonly spoken contractions, so as not to posslbly degrade readability. The use of apostrophes to indicate omissions is varying, it is considerably less frequent than in English publications.

There are several contractions in the Latin language. For example, the Latin verb "volo" (meaning "I want") would originally be negated by the phrase "non volo" (I do not want); after years of elision, however, the phrase became the new word "nolo" (I do not want). This is seen in other uses of the verb; for example, "volunt" (they want) originally being negated "non volunt" (they do not want), but becoming the contraction "nolunt" (they do not want). Similarly, there were the forms "malo/malumus/malunt" for "magis volo", which meant "I want more"; that is, "I prefer".

In Ancient Greek there are several types of contraction, for example in verbs with a stem in ε (epsilon) affect their conjugations. There are also α (alpha) and ο (omicron) contractions in verbs, but ε contractions also happen in nouns and verbs. Example: phil-e-o, I love (Latin transcription for clarity). To the verb stem, phil-, usually the endings -ō, -eīs, -eī, -omen, -ete, -ousin are added. But with the -e-, they go to philō, phileīs, phileī, philoumen, phileite, philousi (that is, I love, you love, he loves, we love, you love, they love)

Some contractions in rapid speech include ～っす (-ssu) for です (desu) and すいません (suimasen) for すみません (sumimasen). では (dewa) is often contracted to じゃ (ja). In certain grammatical contexts the particle の (no) is contracted to simply ん (n).

When used after verbs ending in the conjunctive form ～て (-te), certain auxiliary verbs and their derivations are often abbreviated. Examples:

The ending ～なければ (-nakereba) can be contracted to ～なきゃ (-nakya) when it is used to indicate obligation. It is often used without an auxiliary, e.g. 行かなきゃ（いけない） (ikanakya (ikenai)) "I have to go."

Other times, contractions are made to create new words or to give added or altered meaning:

• The word 何か (nanika) "something" is contracted to なんか (nanka) to make a colloquial word with a meaning along the lines of "sort of," but which can be used with almost no meaning. Its usage is as a filler word is similar to English "like."
• じゃない (ja nai) "is not" is contracted to じゃん (jan) which is used at the end of statements to show the speaker's belief or opinion, often when it is contrary to that of the listener, e.g. いいじゃん！ (ii jan!) "What, it's fine!"
• The commonly used particle-verb phrase という (to iu) is often contracted to ～って／～て (-tte/-te) to give a more informal or noncommittal feeling.
• といえば (to ieba), the conditional form of という (to iu) mentioned above, is contracted to ～ってば (-tte ba) to show the speaker's annoyance at the listener's failure to listen to, remember, or heed what the speaker has said, e.g. もういいってば！ (mō ii tte ba!) "I already told you I don't want to talk about it anymore!"
• The common words だ (da) and です (desu) are older contractions that originate from である (de aru) and でございます (de gozaimasu). These are fully integrated into the language now, and are not generally thought of as contractions.

Various dialects of Japanese also use their own specific contractions which are often unintelligible to speakers of other dialects.

• Relaxed pronunciation
• Elision
• Synalepha
• Contraction (phonology)

• Common English contractions