X chromosome
noun
- Genetics (in humans and other mammals) a sex chromosome, two of which are normally present in female cells (designated XX) and only one in male cells (designated XY)【遗传】（人类和其他哺乳动物的）X染色体（性染色体的一种, 两个此种染色体一般存在于雌性细胞中［标为XX］, 仅一个存在于雄性细胞中［标为XY］）。比较Y CHROMOSOME.