/ Dictionary / Index A arapaima: Meaning and Definition of Find definitions for: ar•a•pai•ma Pronunciation: (ar"u-pī'mu), [key] — n. a large freshwater fish, Arapaima gigas, of Brazil and Guiana, reputed to reach a length of 15 ft. (4.5 m) and a weight of 500 lb. (225 kg). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Arapahoe Arapesh Related Content Daily Word Quiz: candid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language