Fire

From Memory Alpha, the free Star Trek reference.

Fire is a form of combustion. It generally creates heat and can cause burn injuries. Some lamps will use an open flame to provide light similar to candles.

The preindustrial civilization of Barkon IV incorrectly believed that fire was one of the four basic elements of the universe, along with rock, sky and water. By exposing wood to flame, it was believed that the fire in the wood was encouraged to show itself. (TNG: "Thine Own Self")

The dragons of Berengaria VII breath fire. (TOS: "This Side of Paradise")

Other things that "Fire" may refer to include:

• The Fire Plains of Vulcan.
• Sand fire, a naturally occurring weather phenomenon on Vulcan.
• The Dream of the Fire, a Klingon novel by K'Ratak.
• Firenut, a blend of coffee.
• Fire salt, a substance mined by the Tellarites.
• The Fire Caves of Bajor (also referred to as the Fire Caverns).
• A plasma fire, caused by the burning of ruptures in a plasma conduit on a starship.

It could also refer to:

• The Star Trek: Voyager episode "Cold Fire".
• The Star Trek: Enterprise episode "Cease Fire".