/ Dictionary / Index F freeboard deck: Meaning and Definition of Find definitions for: free'board deck" Pronunciation: [key] — Naut. Naut. (on a cargo vessel) the uppermost deck officially considered to be watertight: used as the level from which the Plimsoll marks are measured. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. freeboard freeboard length Related Content Daily Word Quiz: mamba Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language