Definition - The inserting of vowels between consonants to make a word easier to pronounce.

Example -
Pronouncing the word grievous ('gree - vous) as gree - vee' - ous.

Etymology -
It means "opening" or "unfolding" in Greek.

Oxford English Dictionary -
Its first citation is from 1895:
"Anaptyxis … the development of a vowel between two consonants."
(P. Giles, Manual of Comparative Philology, 169)

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