flamethrower
A weapon designed to launch fire over a distance, generally using pressurized-gel that either ignites in contact with the air or is otherwise lit as it exits the nozzle. The gel sticks to anything that it touches as it burns. Has a distinctive whoosh sound.
It has been used throughout World War I and World War II and saw limited use as late as the Vietnam war, usually to attack enemies inside fortifications or hiding among the trees.
Warhammer 40k makes extensive use of flamethrowers. It is also the primary weapon for the Pyro in Team Fortress 2.