/ Dictionary / Index L linebacker: Meaning and Definition of Find definitions for: line•back•er Pronunciation: (līn'bak"ur), [key] — n. Football. a player on defense who takes a position close behind the linemen. the position played by this player. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: linebacker (Thesaurus) lineation linebred Related Content Daily Word Quiz: grimace Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language