/ Dictionary / Index E equilateral: Meaning and Definition of Find definitions for: e•qui•lat•er•al Pronunciation: (ē"kwu-lat'ur-ul, ek"wu-), [key] — adj. having all the sides equal: an equilateral triangle. —n. a figure having all its sides equal. a side equivalent, or equal, to others. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: equilateral (Thesaurus) equiform equilateral hyperbola Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language