/ Dictionary / Index S SLA: Meaning and Definition of Find definitions for: SLA Pronunciation: [key] Special Libraries Association. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. SL slab Related Content Daily Word Quiz: cetacean Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language