|Sound change and alternation|
In phonology, syncope (//; from Ancient Greek: συγκοπή, romanized: sunkopḗ, lit. 'cutting up') is the loss of one or more sounds from the interior of a word, especially the loss of an unstressed vowel. It is found in both synchronic and diachronic analyses of languages. Its opposite, whereby sounds are added, is epenthesis.
Synchronic analysis studies linguistic phenomena at one moment of a language's history, usually the present, in contrast to diachronic analysis, which studies a language's states and the patterns of change across a historical timeframe. In modern languages, syncope occurs in inflection, poetry, and informal speech.
In languages such as Irish and Hebrew, the process of inflection can cause syncope:
If the present root form in Irish is the result of diachronic syncope, synchronic syncope for inflection is prevented.
Sounds may be removed from the interior of a word as a rhetorical or poetic device: for embellishment or for the sake of the meter.
Various sorts of colloquial reductions might be called "syncope" or "compression".
Contractions in English such as "didn't" or "can't" are typically cases of syncope.
In historical phonology, the term "syncope" is often limited to the loss of an unstressed vowel, in effect collapsing the syllable that contained it: trisyllabic Latin calidus (stress on first syllable) develops as bisyllabic caldo in several Romance languages.
A syncope rule has been identified in Tonkawa, an extinct American Indian language in which the second vowel of a word was deleted unless it was adjacent to a consonant cluster or a final consonant.
the pronunciation of library as /laɪbri/