Plasma weapon
A plasma weapon was a type particle weapon that used plasma as a means of inflicting damage to the target. ()

Specifications
Ship-mounted and hand-held directed energy plasma weapons fired plasma bullets, () disruptor bursts, () modulating plasma pulses, () concentrated plasma charges, () or a beam similar to phase weapon fire. () 

Some types of phasers that fired a forced plasma beam were also classified as plasma weapons. () Plasma weapons were also used as torpedoes, bombs, and explosives. (; ; )

History 
In the late-15th century, the Turei and their allies used plasma bombs to destroy the surface of the Vaadwaur homeworld. ()

During the early- to mid-22nd century, Earth Cargo Service freighters were commonly equipped with low-yield plasma cannons, often referred to as "pop-guns", designed only to break up asteroids and meteors. The captains of these freighters, however, would often upgrade the cannons for more powerful ones the first chance they got. ()

 was also equipped with several plasma cannons during the first days of its mission, but was eventually upgraded with the more advanced phase cannons. () Enterprises  was equipped with dual plasma cannons. () Nausicaan pirates of this era also utilized plasma cannons on their ships. ()

Plasma rifles were a common hand-held plasma weapon used by many species in the 22nd century. These weapons were used by Human civilians and carried on Earth starships even after the advent of phase weapons. While not particularly high-yield, they were capable of killing a target. The Jem'Hadar and the Na'kuhl made use of more powerful plasma rifles several centuries later. (; )

In the 23rd century, the plasma torpedo was an extremely powerful torpedo weapon composed of high-energy plasma used by Romulan forces on their Bird-of-Prey ships. They were first encountered by Starfleet when a Romulan ship destroyed several of the Federation's outposts near the Romulan Neutral Zone with these torpedoes. () 

In the 2270s, extremely powerful plasma weaponry was used by V'ger during its journey back to Earth. V'ger generated plasma energy devices of variable yields of which the exact composition or guidance system could not be determined. The weaponry could be set to destroy starships and space stations, or to be set to a level hundreds of times more powerful to devastate the entire surface of a planet. ()

According to Captain Kathryn Janeway, the fact that Starfleet ships were equipped with plasma weapons was taken for granted in the year 2373. While, in the year 2293, this plasma weaponry was not yet in use and the technologies were still in the early stages of development. () These 24th century plasma weapons included plasma charges and plasma warheads. (; )

Plasma torpedoes were still used by the Romulans in the 24th century. () Kazon  warships and Cardassian orbital weapon platforms also used them. (; ) Cardassian missiles were equipped with an omni-directional plasma wave weapon to defend themselves from destruction before they had completed their mission. ()

The hand phasers used by the Ferengi and weapon implants used by the Borg drones, who in 2369 murdered the entire staff of the Ohniaka III Research Station, emitted a forced plasma beam. () A plasma phaser was also being developed by Starfleet as an anti-Borg weapon in 2366. ()

Improvised uses
Plasma could also be used as a weapon in several improvised ways. 
 Warp plasma could be vented into space by a starship. The plasma could then be ignited with particle weapons. The resulting explosion was powerful enough to disable the propulsion of ships enveloped in the plasma field. () 
 A ship using tetryon plasma as warp plasma could also vent it out in front of pursuing vessels to cause their warp drive to stall. ()
 An EM pulse could be fired at a star to trigger a destructive solar plasma ejection. ()
 When a reactor core was attacked with a tachyon beam, a plasma surge in the core would send a plasma burst back along the beam to disable the attacking ship by overloading its power grid and causing relay burnouts. ()
 A modified laser scanner combined with a plasma inverter could be used to fire off an incapacitating plasma shock. ()
 Exposure to plasma fire could cause varying degrees of burns on the body. () Being thrown into a plasma fire could even cause a person to vaporize. ()

Types of plasma weapons
 Ferengi phaser
Forced plasma beam
 Plasma bomb
 Plasma cannon
 Plasma charge
 Plasma shock
 Plasma phaser
 Plasma rifle
 Disruptor burst
 Modulating plasma pulse
 Plasma bullet
 Plasma torpedo
 Plasma warhead
 Plasma wave

de:Plasmawaffe
Directed energy weapons