/ Dictionary / Index S subglacial: Meaning and Definition of Find definitions for: sub•gla•cial Pronunciation: (sub-glā'shul), [key] — adj. beneath a glacier: a subglacial stream. formerly beneath a glacier: a subglacial deposit. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. subgingival subgrade Related Content Daily Word Quiz: blanch Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language