Entry 2 senses Webster, 1913 Synizesis · Syn·i·ze·sis · IPA /sɪnɪˈziːsɪs/ 01 n. An obliteration of the pupil of the eye. 1. An obliteration of the pupil of the eye.(Med.) 2. A contraction of two syllables into one; synecphonesis.(Gram.)