GEO or Geo may refer to any of the following:

In computational & scientific use:

  • GEO (magazine), a popular scientific magazine
  • GEO 600, a detector for gravitational radiation
  • Global Environment Outlook, an environmental assessment produced by the United Nations
  • Geo (microformat), a microformat for marking up geographical coordinates in (X)HTML
  • Geo URI, a IETF proposed standard for making URIs for physical locations
  • Gene Expression Omnibus, a National Center for Biotechnology Information database for gene expression
  • Geostationary Earth orbit, another name for geostationary orbit, a geosynchronous orbit directly above the Earth's equator.

In commercial use:

  • Geo (marketing), a discipline within marketing analysis
  • Geo TV, a leading television channel in Pakistan
  • Geo (automobile), a defunct brand of entry-level cars produced by General Motors
  • GEO Group, a prison corporation


  • Geo. is sometimes an abbreviation of the name George
  • Geo Bogza, a Romanian poet and essayist
  • Geo Stelar is the main protagonist in Mega Man Star Force
  • Christian Geo Heltboe, Danish comedian known by his middle name Geo
  • Geo, a fictional character on the Nick Jr. television show, Team Umizoomi

As a group:

  • Grupo Especial de Operaciones, a division of the Spanish police
  • General Education Officer, the basic rank of teachers of the Ministry of Education in Singapore
  • Group on Earth Observations, an intergovernmental organization

As a place:

  • GEO, the IATA code for Cheddi Jagan International Airport
  • Estadio Casas GEO, stadium in Mexicali, Mexico
  • Geo (landscape), a creek (inlet) or gulley in the Orkney and Shetland Islands
  • The IOC country code and three letter country code for Georgia, a Eurasian country
  • Geo City, a fictional city in the videogame Raw Danger

As a prefix: geo- is taken from the Greek word γη or γαια meaning "earth", usually in the sense of "ground or land". Geo- is thus a prefix for many words dealing in some way with the earth, including:

Look up geo-, geography, geology, geopolitics, or geothermal in Wiktionary, the free dictionary.
  • Geography, the study of the Earth and its features
    • Geology, the study of the Earth's structure
    • Geopolitics, the analysis of history, geography and social science with respect to international politics
    • Geodesy, also known as geodetics, the study of the measurement and representation of the earth
  • Geometer moth, the larvae of which appear to "measure the earth" as they move in a looping fashion
  • Geometry, the study of spatial relationships
    • Geocentric, a model of the universe that places the earth at its centre
      • Geostationary orbit, a circular orbit directly above the Earth's equator
      • Geosynchronous orbit, an orbit that has the same period as the Earth's sidereal rotation
  • Geothermal (geology), heat sources from within the Earth
    • Geo-exchange, a heating and cooling system
  • Geocaching, an outdoor activity that involves using navigational techniques to find geocaches
  • Geocoding or GeoTagging, encoding coordinates in to features, images, web pages and other data records
    • Geolocation, the science of determining the real-world location of a website or website visitor