Breadcrumb Home > Dictionary > Index D deficient number: Meaning and Definition of Find definitions for: defi'cient num'ber Pronunciation: [key] — Math. Math. a positive number that is greater than the sum of all positive integers that are submultiples of it, as 10, which is greater than the sum of 1, 2, and 5. Also calledCf. abundant number, perfect number. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. deficient deficit TrendingHere are the facts and trivia that people are buzzing about. The Book of Philippians: Summary Current Events This Week: May 2023 Preamble of the United Nations Charter Queen Victoria Books of the Bible: New Testament Books in Order The 88 Recognized Constellations ✖ Related Content Daily Word Quiz: miasma Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language