Look up XX, xx, or x_x in Wiktionary, the free dictionary.

XX or xx may refer to:

• 20 (number), Roman numeral XX

Film and TV

• XX (film), a 2017 anthology horror film
• "XX", an episode of CSI: Crime Scene Investigation (season 4)
• XX, the production code for the 1969 Doctor Who serial The Seeds of Death
• XX (web series), a 2020 South Korean web series
• XX (organization), a fictional organisation in the comic and game XIII

Genetics

• XX sex chromosomes, in the XY sex-determination system
• XX sex chromosomes, in the XO sex-determination system
  • a female, an organism producing ova gametes that fuse with the male gamete during sexual reproduction, typically having two X chromosomes
  • XX male syndrome, also known as de la Chapelle syndrome, a rare congenital intersex condition resulting in a phenotypical male with two X chromosomes
  • XX gonadal dysgenesis, a type of female hypogonadism resulting in non-functioning ovaries

Music

• The xx, a British indie band
• X_______X (band), a Cleveland no wave band

Organisations

• XX Bomber Command, an inactive United States Air Force unit
• XX Corps (disambiguation)
• Legio XX Valeria Victrix or Legion XX, a legion of the Roman Empire

Other uses

• XX (novel), a 2020 novel by Rian Hughes
• XX System or Double-Cross System, a British deception operation in the Second World War
• Les XX, a group of twenty Belgian painters
• Dos Equis or XX, a brand of Mexican beer
• xx, to express exponentiation in the initial version of the FORTRAN programming language

See also

• All pages with titles containing XX
• 20 (disambiguation)
• Double Cross (disambiguation)
• X (disambiguation)
• XXX (disambiguation)
• XXXX (disambiguation)