crasis
Concise Oxford English Dictionary © 2008 Oxford University Press:
crasis /ˈkreɪsɪs/
▶noun (pl. crases /-siːz/) Phonetics a contraction of two adjacent vowels into one long vowel or diphthong.
– origin C16: from Gk krasis ‘mixture’.
'crasis' also found in these Oxford entries:

