OD

OD or Od may refer to:

Education

 * Old Diocesan, a former pupil of Diocesan College
 * Old Dunelmian, a former pupil of Durham School

Medicine

 * OD or o.d., an abbreviation used in medical prescriptions for omne in die or "once daily" both meaning "take once every day"
 * Doctor of Optometry (O.D.)
 * Oculus dexter, ocular dexter, or ocularis dexter, meaning "right eye" in general ophthalmologic or optometric usage, particularly in eyeglass prescriptions
 * Osteochondritis dissecans, a medical disease affecting the joints of both humans and animals
 * Overdose, the inadvertent drug effects of the user rendered unresponsive or fatally succumbed due to unsophistication of self-medicating being unaccustomed to quantities greater than recommended

Music

 * Oblivion Dust, a Japanese rock band
 * Old Dominion (band), an American country music band
 * One Direction, a British/Irish pop music band
 * Orphei Drängar, a Swedish male choir
 * The OD EP, a 2012 extended play by Danny Brown
 * Overly Dedicated, a 2010 mixtape by Kendrick Lamar
 * "O.D", a song by Sunna from the album One Minute Science (2000)
 * "OD", an alternative name for the song "DTM" by SZA from Lana (2024)

Organizations

 * Batik Air Malaysia (IATA airline code OD)
 * Ordnungsdienst, Jewish order service in ghettos during the war
 * Organization development

People and characters

 * Super OD, a Ghanaian actor
 * O.D (Gatchaman Crowds), a character in the anime series Gatchaman Crowds
 * Ód or Óðr, a Nordic god

Places

 * Odisha, India
 * Stormarn (district), Germany (vehicle plate code OD)

Science and technology

 * Optical density
 * Outside diameter (also: O.D.), cylinder or pipe external diameter
 * Ordnance datum, in Britain, an Ordnance Survey data point
 * od (Unix), a Unix program
 * Object Desktop, a suite of skinning and customization programs by Stardock, or ObjectDock, another program by the same company
 * Optical disc
 * Organization development, the study of organizational change and performance
 * Ordinal definable set, a set requiring only finitely-many ordinals to define under first-order logic.

Other uses

 * OD (video game), an upcoming video game developed by Kojima Productions and published by Xbox Game Studios
 * Od language, an Indo-Aryan language of Pakistan
 * Odic force or Od, a life force
 * Occupation Double, a Quebec reality show that started in 2003
 * Official Declaration, part of Latter-day Saint scripture
 * Olive drab, a color, particularly of some United States Army uniforms
 * Online dating
 * Original dance, the second part of an ice dancing competition
 * Order of Distinction, a civil honour of Jamaica
 * OD - original designation in Taxonomy