antepenult vs antepenultimate

antepenult and antepenultimate both are nouns.

Word	Noun	Adjective	Verb	Adverb
antepenult	Yes	No	No	No
antepenultimate	Yes	Yes	No	No

As nouns, antepenult and antepenultimate are synonyms defined as:

antepenult and antepenultimate: the 3rd syllable of a word counting back from the end

Other synonyms of antepenult include antepenultima.

antepenult (noun)	antepenultimate (noun)
the 3rd syllable of a word counting back from the end	the 3rd syllable of a word counting back from the end

antepenult (adjective)	antepenultimate (adjective)
	third from last