vocal fold vs plica

vocal fold and plica both are nouns.

Word	Noun	Adjective	Verb	Adverb
vocal fold	Yes	No	No	No
plica	Yes	No	No	No

As nouns, plica is a hypernym of vocal fold; that is, plica is a word with a broader meaning than vocal fold:

vocal fold: either of two pairs of folds of mucous membrane projecting into the larynx
plica: a folded part (as in skin or muscle)

Other hypernyms of vocal fold include fold.

vocal fold (noun)	plica (noun)
either of two pairs of folds of mucous membrane projecting into the larynx	a folded part (as in skin or muscle)