Firebrick

Part of speech: noun

Definitions

1. A special kind of brick made to resist high temperatures, typically employed in kilns and furnaces for industrial purposes
2. This material is specifically formulated to endure severe heat, commonly used in fireplaces and heat-intensive applications
3. A type of brick made to tolerate very high temperatures, often used in heating or industrial settings

Etymology: A firebrick is about as literal as compounds get: fire plus brick, a brick made to survive fire. The surprise lies in the plain meaning of its parts. Brick itself has been in English since Old English times, while "fire" was already an ancient word, so the compound simply describes a brick that can endure the furnace without cracking or melting. Its job is the whole point of its name. The word is used for the refractory bricks that line fireplaces, kilns, furnaces and similar high-temperature structures. Ordinary clay bricks would crumble under sustained heat, so firebricks are made from materials that withstand it, which is why the term names a function rather than a shape or colour.