/ Dictionary / Index S spontaneous abortion: Meaning and Definition of Find definitions for: sponta'neous abor'tion Pronunciation: [key] miscarriage (def. 1). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. spontaneous spontaneous combustion 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