The BLU-82 daisy cutter is a bomb used by the US Military, specifically the USAF. The origins of the name 'daisy cutter' (which is an understatement, see daisy) are disputed. It is generally supposed to derive from Vietnam War-era usage of the device, but in that era, it was known as Commando Vault when used to clear landing fields (rumored to be able to clear a 300 foot diameter landing zone) for helicopters by being dropped from a C-130 transport aircraft, or as Big Blue 82 for the bomb on its own. In the Vietnam war, Daisy Cutter was generally used to refer to a standoff bomb fuse.

It is commonly reported to be a thermobaric bomb, but this is not the case. The BLU-82B is a conventional explosive device incorporating both agent and oxidizer (ammonium nitrate, aluminum powder, and polystyrene). It is fitted with a fuse extension to provide detonation 1 to 6 feet (0.3 to 2 m) above ground, minimizing the cratering effect and maximizing the blast effect. The daisy cutter was originally used to create an instant clearing in dense jungle for helicopter landing zones. It can also be used to clear minefields of pressure sensitive mines or as an anti-personnel bomb relying on its extreme blast effects. The BLU-82 must be parachute launched from the back of a transport plane, typically a C-130, because of its large size. The Air Force successfully lobbied for the development of an even larger, 30,000 lb (13.6 t) weapon, which would be deployed from a traditional bomber (i.e. B-52, B-2, B1). (See Massive Ordnance Air Blast bomb)

The Daisy Cutter became better known to the public when it was used in the 2001 U.S. Attack on Afghanistan to clear deeply entrenched Taliban fighters and suspected cave strongholds in the Tora Bora mountain range. The popularization of the nickname Daisy Cutter for the BLU-82 probably was part of the psychological warfare campaign, to give a jocular or even 'cute' name to a weapon of massive destructive capability.

It is primarily used today in combat zones such as Afghanistan as a psychological warfare agent. The atmospheric overpressure and seismic event are terrifying to all on the ground. Tests as a landmine-clearing weapon in the 1991 Second Gulf War against Iraq came up inconclusive; later in the campaign, it was used in a few instances for its psychological effect.