In phonology, apocope (/əˈpɒkəpiː/) is the loss (elision) of one or more sounds from the end of a word, and especially the loss of an unstressed vowel.
Apocope comes from Greek ἀποκοπή apokopḗ from ἀποκόπτειν apokóptein, “cutting off”, from ἀπο- apo-, “away from” and κόπτειν kóptein, “to cut”.
In historical phonetics, the term apocope is often (but not always) limited to the loss of an unstressed vowel.
In the Estonian language and Sami languages, apocopes help explain the forms of grammatical cases. For example, a nominative is described as having apocope of the final vowel, whereas the genitive does not. Throughout its history, however, the genitive case marker has also undergone apocope: linn (a city) vs linna (of a city), is derived from linna and linnan, respectively. In the genitive form, final /n/, while being deleted, blocked the loss of /a/. In spoken Finnish, the final vowel is sometimes omitted from case markers.
Some languages have apocopations internalized as mandatory forms. In Spanish and Italian, for example, some adjectives that come before the noun lose the final vowel or syllable when they precede a noun (mainly) in the masculine singular form. In Spanish some adverbs, cardinal and ordinal numbers have apocopations as well.