/ Dictionary / Index Y Y chromosome: Meaning and Definition of Find definitions for: Y chromosome Pronunciation: [key] — Genetics. Genetics. a sex chromosome of humans and most mammals that is present only in males and is paired with anchromosome. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Yb Y.C.L. Related Content Daily Word Quiz: impetuous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language