in Chemistry, a prefix meaning produced by heating.

An aluminum powder used in pyrotechnics for white flame and brightness;

The fire zone in Metroid Fusion

Mineral Insulated Copper Clad cable, a type of fire resistant electrical cable

Pyro (comics), a fictional fire-controlling mutant in Marvel Comics's X-Men titles

Pyrotechnics, flames and explosives used in special effects;

A playable class in Team Fortress Games

Pyromaniac, a person who is obsessed with fire;

Jargon for pyrotechnic fasteners, also commonly known as explosive bolts.

Pyro 2, an ASCII game

Pyro Studios, a computer game developer based in Madrid

Pyro Desktop, a desktop environment for Linux built on Mozilla Firefox.

Fire itself – Pyr means "fire" in Greek;

in Organic Chemistry, a prefix indicating a dimeric acid anhydride, e.g., pyrophosphoric acid.