/ Dictionary / Index X XL: Meaning and Definition of Find definitions for: XL Pronunciation: [key] extra large. extra long. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: xl (Thesaurus) Xizang x-line Related Content Daily Word Quiz: immense Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language