noun
gun turret
Refers to a rotating armored structure on a warship, tank, or fortification that houses and protects a gun and its crew.
戦艦の砲塔が一斉に火を噴いた。
The battleship's gun turrets fired all at once.
この戦車は自動装填装置付きの砲塔を備えている。
This tank is equipped with a gun turret with an autoloader.
砲台 is a gun battery or fixed gun emplacement, often on land, while 砲塔 is a rotating armored turret, typically on a ship or tank.
Compound of 砲 (ほう, 'gun, cannon') and 塔 (とう, 'tower, turret'). The exact historical derivation is uncertain, but the spelling is conventionally associated with the meaning 'gun turret'.