/ Dictionary / Index E erythroblastosis: Meaning and Definition of Find definitions for: e•ryth•ro•blas•to•sis Pronunciation: (i-rith"rō-bla-stō'sis), [key] — n. Pathol. the presence of erythroblasts in the blood. Also calledthis condition in the fetus or newborn, usually caused by an Rh incompatibility between mother and baby. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: erythroblastosis (Thesaurus) erythroblast Erythrocin Related Content Daily Word Quiz: rotund Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language