/af"euh sis/ , n. Historical Ling.
the disappearance or loss of an unstressed initial vowel or syllable, as in the formation of the word slant from aslant.
[ 1880; áphesis a letting go, equiv. to aphe- (var. s. of aphiénai to let go, set free; ap- AP- 2 + hiénai to send) + -sis -SIS ]