Turbolaser
From the Encyclopedia of Speculative Fiction - http://encyclopedia.wizards.pro
The turbolaser was the immensely scaled up version of the blaster and laser cannon. It was a heavy laser cannon equipped with turbine generators and large banks of capacitors, which allowed the weapon to build up and store far more powerful laser bursts than standard lasers, allowing them to pierce the defenses of heavily protected targets. These weapons, because they needed to build up energy for their powerful blasts, also tended to have a slower rate of fire than their brethren.
Turbolasers could also be emplacement weapons, with power to match their immense proportions. Turbolaser turrets installed on the first Death Star were unable to lock on to the nimble Rebel starfighters that were attacking the station during the Battle of Yavin.