/ Dictionary / Index L line mark: Meaning and Definition of Find definitions for: line' mark" Pronunciation: [key] a trademark covering all items of a particular product line. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. lineman's pliers linen Related Content Daily Word Quiz: benevolent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language