Cavity and Furnace

Cavity noun - A sunken area forming a separate space.

Furnace and cavity are semantically related. In some cases you can use "Furnace" instead a noun "Cavity".

Furnace noun - An enclosed chamber in which heat is produced to heat buildings, destroy refuse, smelt or refine ores, etc..

Cavity and furnace are semantically related. Sometimes you can use "Cavity" instead a noun "Furnace".