Mertens function

XY or Xy may refer to:

• Xy (digraph), a digraph of the Romanized Popular Alphabet, used to write Hmong
• XY (magazine), a gay male youth magazine that also operated a personals website
• XY sex-determination system, a system in biology
• XY model, a model in physics
• $xy$ coordinates, a system used to locate a point in two dimensions according to the cartesian coordinate system
• Xy, a member of the band Samael
• Aktenzeichen XY … ungelöst

See also

• X&Y, an album by Coldplay
• Pokémon X and Y, handheld video games for the Nintendo 3DS
• YX (disambiguation)
• Xyz (disambiguation)