Breadcrumb Home > Dictionary > Index P piranha: Meaning and Definition of Find definitions for: pi•ra•nha Pronunciation: (pi-rän'yu, -ran'- or, often, -rä'nu, -ran'u), [key] — pl. -nhas, -nha. any of several small South American freshwater fishes of the genus Serrasalmus that eat other fish and sometimes plants but occasionally also attack humans and other large animals that enter the water. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: piranha (Thesaurus) Piranesi Pirapóra ✖ Related Content Daily Word Quiz: deracinate Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language