XO

XO may refer to:

• XO-Care Most advanced dentist equipment
• Executive officer in the military
• Christian Allen, New College Entz
• Executive order, an edict by a member of the executive branch of a government
• Xanthine oxidase, an enzyme that catalyzes the oxidation of hypoxanthine to xanthine
• Crystal oscillator, an electronic circuit that uses the mechanical resonance of a vibrating crystal to create an electrical signal with a precise frequency
• XO, the now-deprecated abbreviation for crystal oscillators on electrical schematic diagrams
• XO, a grade of cognac, meaning "extra old"
• XO, the IATA code for Spain's LTE International Airways
• XO Communications, a telecom company
• XO sauce, a spicy seafood sauce
• XO Telescope and its related exo-planet survey

Music

• XO (album) by singer-songwriter Elliott Smith
• "XO", a song on Fall Out Boy's third studio album, From Under The Cork Tree
• XO (Leathermouth album), Leathermouth's debut album
• "XOXO", a song on Gunnie Sanotchra's 2009 studio album, Girl Crazy
• "XO", alias for Toronto-based musician The Weeknd

See also

• Chi Omega ("ΧΩ"), a National Panhellenic Conference women's fraternity
• Eastern Orthodoxy Christianity (from the Greek: Χριστιανός Ορθόδοξος, Xristianos Orthodoksos)
• Hugs and kisses, sometimes written as a sequence of XOs
• OLPC XO-1 laptop, produced by the One Laptop per Child association
• Tic-tac-toe, a game using X's and O's
• X0 (disambiguation)
• XOXO, an XML microformat