/ Dictionary / Index L lower mast: Meaning and Definition of Find definitions for: low'er mast' Pronunciation: (lō'ur), [key] — Naut. Naut. the lowermost spar of a compound mast, stepped in the hull of a vessel and carrying a topmast and any other upper spars. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Lower Lakes Lower Merion Related Content Daily Word Quiz: arboreal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language