Fire retardant
A fire retardant is a substance that helps to delay or prevent
combustion. Fire retardants are commonly used in
fire fighting. Water is the most commonly used fire retardant, but the phrase typically refers to chemical retardants. It can also refer to a coating over an object, such as a spray retardant to prevent Christmas trees from burning.
See more at Wikipedia.org...
fire-retardant
Adjective
1. difficult to burn
(synonym) fire-resistant, fire-resisting, fire-resistive
(similar) noncombustible, incombustible
fire retardant