See also: xx and x x



Etymology 1Edit



  1. A Roman numeral representing the number 20.
Alternative formsEdit
See alsoEdit

Etymology 2Edit

From X chromosome, so named by Hermann Henking in 1890 because it had some baffling properties.


XX ‎(not comparable)

  1. Having a female configuration of chromosomes.
    • 2001, Kenneth L. Becker (ed), Principles and Practice of Endocrinology and Metabolism, page 857, ISBN 0781717507.
      An autosomal recessive gene causes gonadal dysgenesis in XX individuals, and several distinct entities have been identified.
    • 2007, Fima Lifshitz (ed), Pediatric Endocrinology, Volume 2, page 358, ISBN 1420055232.
      If a Y chromosome is present in an XX-karyotyped individual, gonadal removal is necessary due to the risk of gonadoblastoma.
    • 2009, Gerald N. Callahan, Between XX and XY: Intersexuality and the Myth of Two Sexes, page 30, ISBN 1556527853.
      The group at John Hopkins, as well as many others, dropped the "true sex" policy (such as XX or XY) and adopted the "optimal gender" policy for assigning sex to sexually ambiguous children.
  2. (said of birds) Having a male configuration of chromosomes.
See alsoEdit