Breadcrumb Home > Dictionary > Index G guesstimate: Meaning and Definition of Find definitions for: guess•ti•mate Pronunciation: (v.ges'tu-māt"n.ges'tu-mit, -māt"), [key] — v., n. -mat•ed, -mat•ing, —v.t. to estimate without substantial basis in facts or statistics. —n. an estimate arrived at by guesswork. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: guesstimate (Thesaurus) guess guesswork TrendingHere are the facts and trivia that people are buzzing about. Jewish Holidays, 2010-2030 (A.M. 5770-5791) Western Christian Holidays, 2010-2030 12 Steps to a New Year New Year's Resolution to Slim Down? Martin Luther King Speeches Books of the Bible: Old Testament Books in Order ✖ Related Content Daily Word Quiz: cognoscenti Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language