/ Dictionary / Index B biological parent: Meaning and Definition of Find definitions for: biolog'ical par'ent Pronunciation: [key] a parent who has conceivedor siredrather than adopted a child and whose genes are therefore transmitted to the child. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. biological oxygen demand biological psychiatry Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language