/ Dictionary / Index H heterozygous: Meaning and Definition of Find definitions for: het•er•o•zy•gous Pronunciation: (het"ur-u-zī'gus), [key] — adj. Biol. having dissimilar pairs of genes for any hereditary characteristic. of or pertaining to a heterozygote. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: heterozygous (Thesaurus) heterozygote heth Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language