Breadcrumb Home > Dictionary > Index Q quadrillion: Meaning and Definition of Find definitions for: quad•ril•lion Pronunciation: (kwo-dril'yun), [key] — n., pl. adj. -lions, -lion, —n. a cardinal number represented in the U.S. by 1 followed by 15 zeros, and in Great Britain by 1 followed by 24 zeros. —adj. amounting to one quadrillion in number. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: quadrillion (Thesaurus) quadrille quadrinomial TrendingHere are the facts and trivia that people are buzzing about. Chinese New Year History, Meaning, and Celebrations Current Events This Week: February 2024 Valentine's Day Valentine's Day History Mardi Gras 30 "Charlie and the Chocolate Factory" Quotes ✖ Related Content Daily Word Quiz: bowdlerize Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language