Contraction (grammar)

A contraction is a shortened version of the written and spoken forms of a word, syllable, or word group, created by omission of internal letters and sounds.

In linguistic analysis, contractions should not be confused with crasis, abbreviations nor acronyms (including initialisms), with which they share some semantic and phonetic functions, though all three are connoted by the term "abbreviation" in loose parlance. Contraction is also distinguished from clipping, where beginnings and endings are omitted.

The definition overlaps with the grammatical term portmanteau (a linguistic blend), but a distinction can be made between a portmanteau and a contraction by noting that contractions are formed from words that would otherwise appear together in sequence, such as do and not, whereas a portmanteau word is formed by combining two or more existing words that all relate to a singular concept which the portmanteau describes.

English has a number of contractions, mostly involving the elision of a vowel (which is replaced by an apostrophe in writing), as in I'm for "I am", and sometimes other changes as well, as in won't for "will not" or ain't for "am not". These contractions are commonly used in speech and in informal writing, though tend to be avoided in more formal writing (with limited exceptions, such as the mandatory form of "o'clock").

The main contractions are listed in the following table (for more explanation see English auxiliaries and contractions).

Some other simplified pronunciations of common word groups, which can equally be described as cases of elision, may also be considered (non-standard) contractions (not enshrined into the written standard language, but frequently expressed in written form anyway), such as wanna for want to, gonna for going to, y'all for you all, ya'll for ya all in the South, and others common in colloquial speech.

In subject–auxiliary inversion, the contracted negative forms behave as if they were auxiliaries themselves, changing place with the subject. For example, the interrogative form of He won't go is Won't he go, whereas the uncontracted equivalent is Will he not go?, with not following the subject.

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