A rock spitter was a type of Yuuzhan Vong launcher for magma missiles, carried alongside plasma cannons aboard their capital ships.
Reflecting their role, rock spitters were sometimes simply called missile tubes. Though mainly seen on larger warships, they were also used by Slayer ships.
It is not clear whether the rock spitter should be considered along with the plasma cannon as a variety of Yaret-Kor. Star by Star and Destiny's Way make a distinction between the two systems, but The Unifying Force uses the terms almost interchangeably.
- The Complete Star Wars Encyclopedia