Apse and Cavity

Apse noun - A domed or vaulted recess or projection on a building especially the east end of a church; usually contains the altar.

Cavity and apse are semantically related. in niche topic. In some cases you can use "Cavity" instead a noun "Apse".

Cavity noun - A sunken area forming a separate space.

Apse and cavity are semantically related. Sometimes you can use "Apse" instead a noun "Cavity".