/ Dictionary / Index A ALS: Meaning and Definition of Find definitions for: ALS Pronunciation: [key] See a.l.s. Pronunciation: [key] autograph letter, signed. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: als (Thesaurus) alright Alsace Related Content Daily Word Quiz: tactful Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language