XX is:

  • Abbreviation for a plane crystallographic group in crystals
  • Abbreviation for female-specific chromosome pair xx, see X - chromosome
  • The Roman numeral for 20
  • Abbreviation for bi- exciton
  • Dos Equis, a beer brand Cerveceria Cuauhtemoc Moctezuma Mexican brewer

XX as distinguishing signs on license plate:

  • Greece: Athens, kept for future approvals
  • Norway: Mosjøen in the province of Nordland
  • Czech Republic: members of the technical staff of diplomatic missions

Xx is:

  • An abbreviation for the Zweitchargierten a fraternity
  • The name for the Thoroughbred ( racehorse, galloping type )
  • A name for the British band The xx and the name of their debut album, see xx ( album )
  • Disambiguation
  • Abbreviation