fire retardant

any substance except plain water that, by chemical or physical action, reduces flammability of fuels or slows their combustion rate —note a fire retardant is often a slurry applied aerially or from the ground during a fire-suppression operation —synonym retardant —see foam, long-term fire retardant, short-term fire retardant, viscous water, wetting agentThis definition last updated 08/08/2008