/ Dictionary / Index I ILS: Meaning and Definition of Find definitions for: ILS Pronunciation: [key] — Aeron. Aeron. instrument landing system. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: ils (Thesaurus) Il Penseroso* Ilse Related Content Daily Word Quiz: penchant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language