Pyro

Pyro comes from the Greek word πυρ (pyr) meaning fire. In English, it can be a prefix pertaining to fire, or it may refer to:

Fire, the rapid oxidation of a material in the chemical process of combustion, releasing heat, light, and various reaction products. Slower oxidative processes like rusting or digestion are not included by this definition.
Pyrotechnics, the science of using materials capable of undergoing exothermic chemical reactions for the production of heat, light, gas, smoke and/or sound
- Pyrotechnician
Pyrotechnic fastener, also known as pyros or explosive bolts
Pyromaniac, someone with a mental illness that wills them to start fires.

In computing and computer games:

Pyro Studios, a computer game developer based in Madrid
PYthon Remote Objects, a remote procedure call library for the Python programming language
Python Robotics, a project designed to create an easy-to-use interface for accessing and controlling a wide variety of real and simulated robots
The Pyro, a playable class in the Team Fortress and Team Fortress 2 games
Pyro 2, an ASCII game
Pyro, a god in Sacrifice (video game)

In entertainment:

Pyro (Transformers), a fictional character
Pyro (comics), a fictional fire-controlling mutant in Marvel Comics's X-Men titles
Fuego (1964 film), also known as Pyro, a suspense film starring Martha Hyer and Barry Sullivan
"Pyro" (song), second single from Kings of Leon's 2010 album Come Around Sundown
The Pyro, a playable character in the 2007 video game, Team Fortress 2.
Mick Pyro, born Michael Tierney, Irish musician and journalist

In military issues:

Other uses:

Pyro (horse), American thoroughbred racehorse
Pyrogallol, when used as a photographic developing agent
A chemistry prefix indicating a dimeric acid anhydride, e.g. pyrophosphoric acid
Mineral Insulated Copper Clad cable, a type of fire resistant electrical cable commonly known as Pyro cable.