The insertion or addition of a letter or syllable in the middle of a word (epenthesis); in medicine, the application or placing of something upon the body.
From Greek epithesis (from epitithemi 'to place upon'). In linguistics, it overlaps with epenthesis.
When you pronounce 'across' as 'a-cross' instead of running the letters together, you're doing a kind of epithesis—adding an extra sound to make it clearer!
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