noun
( biology ) a sex chromosome . In human males each cell has one X chromosome and one Y chromosome. In human females there is never a Y chromosome.
noun
( biology ) a sex chromosome . In human males each cell has one X chromosome and one Y chromosome. In human females there is never a Y chromosome.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005