Banzai charge or Banzai attack 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 Allied forces.

A human wave attack, also known as a human sea attack, is an offensive infantry tactic in which an attacker conducts an unprotected frontal assault with densely concentrated infantry formations against the enemy line, intended to overrun and overwhelm the defenders by engaging in melee combat. The name refers to the concept of a coordinated mass of soldiers falling upon an enemy force and sweeping them away with sheer weight and momentum, like an ocean wave breaking on a beach.