/ Dictionary / Index A ACLU: Meaning and Definition of Find definitions for: ACLU Pronunciation: [key] See American College of Life Underwriters. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. A.C.L.S. acme Related Content Daily Word Quiz: lunar Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language