/ Dictionary / Index P peroneus: Meaning and Definition of Find definitions for: per•o•ne•us Pronunciation: (per"u-nē'us), [key] — pl. -ne•i any of several muscles on the outer side of the leg, the action of which assists in extending the foot and in turning it outward. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: peroneus (Thesaurus) peroneal Peronism Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language