/ Dictionary / Index S spongioblast: Meaning and Definition of Find definitions for: spon•gi•o•blast Pronunciation: (spun'jē-ō-blast", spon'-), [key] — n. Embryol. one of the primordial cells in the embryonic brain and spinal cord capable of developing into neuroglia. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: spongioblast (Thesaurus) spongin spongocoel Related Content Daily Word Quiz: endear Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language