IMO or Imo may refer to:

Biology and medicine

* Irish Medical Organisation, the main organization for doctors in the Republic of Ireland * Intelligent Medical Objects, a privately held company specializing in medical vocabularies * Isomaltooligosaccharide, a mixture of short-chain carbohydrates which has a digestion-resistant property * Idiopathic Massive Osteolysis, a name for Gorham's disease

Maritime

International Maritime Organization The International Maritime Organization (IMO, French: ''Organisation maritime internationale'') is a specialised agency of the United Nations responsible for regulating shipping. The IMO was established following agreement at a UN conference ...

IMO number The IMO number of the International Maritime Organization is a generic term covering two distinct meanings. The IMO ship identification number, is a type of hull number used as a unique ship identifier, and the IMO company and registered owne ...

, a unique identity number issued to seacraft (pattern "1234567") * SS ''Imo'', a 1889 ship involved in the Halifax Explosion

Meteorology

International Meteorological Organization The International Meteorological Organization (IMO; 1873–1951) was the first organization formed with the purpose of exchanging weather information among the countries of the world. It came into existence from the realization that weather systems ...

* Icelandic Meteorological Office

Other

International Mathematical Olympiad The International Mathematical Olympiad (IMO) is a mathematical olympiad for pre-university students, and is the oldest of the International Science Olympiads. The first IMO was held in Romania in 1959. It has since been held annually, except ...

International Meteor Organization The International Meteor Organization (IMO) was formally founded in 1988 from predecessor gatherings over many years. IMO has several hundred members and was created in response to an ever-growing need for international cooperation on amateur and ...

Imo State Imo State ( ig, Ȯra Imo) is a state in the South-East geopolitical zone of Nigeria, bordered to the north by Anambra State, Rivers State to the west and south, and Abia State to the east. It takes its name from the Imo River which flows a ...

, Nigeria * imo.im, a video calling and instant messaging app * IMO (in my opinion), an Internet slang expression * Integration Management Office see Post-merger integration {{disambiguation