| Definition - The contracting of two vowels into either one long vowel or a diphthong.
1. Usually, it involves combining a vowel that is at the end of a word with the one that starts the next word.
2. The term also denotes the internal contracting of Latin words (e.g. the creation of nil from nihil).
Etymology - The word derives from the Greek krasis, mixture.
Oxford English Dictionary - Its first citation is from 1833:
"Avoiding the hiatus…(1) by elision with the apostrophe; and (2) by contracting both syllables into one compound sound, or Crasis."
(E. Robinson tr. Buttmann's Larger Grk. Gram. 60)