antepenult (n.)

"the last but two," 1730, from antepenult (n.), 1610s, abbreviation of Latin antepænultima (syllaba) "last syllable but two in a word," from fem. of antepænultimus, from ante "before" (from PIE root *ant- "front, forehead," with derivatives meaning "in front of, before") + pænultima, from pæne "almost" (a word of uncertain origin) + ultima "last" (see ultimate).