IK or Ik may refer to:

Businesses and organizations

* IK Investment Partners, a European private equity firm * Imair Airlines (IATA code IK) * Iparretarrak, a Basque nationalist organization

Languages

* Ik language (ISO 639 alpha-3 ikx), spoken by the Ik people of Uganda * Inupiaq language (ISO 639 alpha-2), a group of dialects of the Inuit language, spoken in Alaska

Places

* Ik (river), a tributary of the Kama in Bashkortostan and Tatarstan, Russia * Ik (Berd), a tributary of the Berd in Novosibirsk Oblast, Russia * Bolshoy Ik, a tributary of the Sakmara in Bashkortostan and Orenburg Oblast, Russia * Ilm-Kreis, a region in Germany

Science and technology

* IK (gene), a protein-encoding gene * IK code, a classification of resistance to mechanical impacts * ''Internationale Kerze'' (German for "international candle"), an old photometric unit to measure luminous intensity * Inverse kinematics, a branch of mechanics

Other uses

* Ik Onkar, a symbol used in the Sikh religion * Ik people of Uganda * ''The Ik'', a 1975 play by Colin Higgins and Denis Cannan * Imran Khan, Pakistani politician and former cricketer * ''Index Kewensis'', a publication maintained by the Royal Botanic Gardens, Kew * Indigenous knowledge, traditional knowledge held by indigenous peoples * ''International Karate'', a computer game {{disambiguation