anaptyxis

UK: /ˌænæpˈtɪksɪs/ US: (an′əp tik′sis, an′ap-)

WordReference Random House Unabridged Dictionary of American English © 2025

an•ap•tyx•is  (an′əp tik′sis, an′ap-), n., pl. -tyx•es 

(-tik′sēz). 
1. Linguistics epenthesis of a vowel.

• Greek, equivalent. to anaptyk- (stem of anaptýssein to unfold, equivalent. to ana- ana- + ptýssein to fold) + -sis -sis
• Neo-Latin
• 1880–85;

an•ap•tyc•tic  (an′əp tik′tik, an′ap-), an′ap•tyc′ti•cal, adj. 

Collins Concise English Dictionary © HarperCollins Publishers::

anaptyxis / ˌænæpˈtɪksɪs/ noun ( -tyxes / -ˈtɪksiːz/)

1. the insertion of a short vowel between consonants in order to make a word more easily pronounceable

Etymology: 19th Century: via New Latin from Greek anaptuxis, from anaptussein to unfold, from ana- + ptussein to fold