ATF Definition
abbreviation
Bureau of Alcohol, Tobacco, Firearms and Explosives.
Webster's New World
(US, law enforcement) Alcohol, Tobacco and Firearms.
Wiktionary
(automotive) Automatic Transmission Fluid.
Wiktionary
(US, military, aviation) Advanced Tactical Fighter.
Wiktionary
(US, Navy) Auxiliary Tugboat Fleet - a naval fleet tugboat, a fleet tug that can keep up with a fleet on operations.
Wiktionary