What is Banzai charge?

Banzai charge is the term that was used by the Allied forces of World War II to refer to Japanese human wave attacks and swarming staged by infantry units. This term came from the Japanese battle cry "Tennōheika Banzai" , and was shortened to banzai, specifically referring to the tactic used by the Imperial Japanese Army during the Pacific War. This tactic was used when the Japanese commanders of infantry battalions foresaw that a battle was about to be lost, as a last ditch effort in thwarting Soviet and U.S. forces.