/ Dictionary / Index S siliceous: Meaning and Definition of Find definitions for: si•li•ceous Pronunciation: (su-lish'us), [key] — adj. containing, consisting of, or resembling silica. growing in soil rich in silica. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: siliceous (Thesaurus) silicate silicic Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language