Breadcrumb Home > Dictionary > Index L least bittern: Meaning and Definition of Find definitions for: least' bit'tern. Pronunciation: [key] See under (def. 2). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. least least common denominator ✖ Related Content Daily Word Quiz: acronym Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language