Crasis

Crasis (/ˈkreɪsɪs/; from the Greek κρᾶσις, "mixing", "blending") is a type of contraction in which two vowels or diphthongs merge into one new vowel or diphthong, making one word out of two. Crasis occurs in Portuguese and Arabic as well as in Ancient Greek for which it was first described.

In some cases, like in the French examples below, crasis involves the grammaticalization of two individual lexical items into one, but in other cases, like in the Greek examples, crasis is the orthographic representation of the encliticization and vowel reduction of one grammatical form with another. The difference between the two is that the Greek examples involve two grammatical words and a single phonological word and the French examples involve a single phonological word and grammatical word.

In both Ancient and Modern Greek, crasis merges a small word and long word closely connected in meaning.

In Ancient Greek, a coronis (κορωνίς korōnís "curved"; plural κορωνίδες korōnídes) marks the vowel from crasis. In ancient times, it was an apostrophe placed after the vowel (τα᾽μά), but it is now written over the vowel τἀμά, and it is identical to smooth breathing in Unicode. (For instance, τἀμά uses the character U+1F00 ἀ Greek small letter alpha with psili; psili means smooth breathing.) Unlike a coronis, smooth breathing never occurs on a vowel in the middle of a word (although it occurs on doubled rho: πύῤῥος pyrrhos).

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