- the U.S. department consisting of practically all military aviation forces, established July 26, 1947.
- (lowercase) a similar department in any military organization.
- (lowercase) (formerly) the largest unit in the U.S. Army Air Forces.
- (lowercase) a unit of U.S. Air Force command between an air division and an air command.
- (sometimes lowercase) the military unit of a nation charged with carrying out military operations in the air.
- British. Royal Air Force.
- the branch of a nation’s armed services primarily responsible for air warfare
- (as modifier)an air-force base
- a formation in the US and certain other air forces larger than an air division but smaller than an air command
1917, from air (n.1) + force (n.); first attested with creation of the Royal Air Force. There was no United States Air Force until after World War II. The Air Corps was an arm of the U.S. Army. In 1942, the War Department reorganized it and renamed it Army Air Forces. The National Security Act of 1947 created the Department of the Air Force, headed by a Secretary of the Air Force, and the U.S.A.F.