A person from below ground level.

A resident of an underground community or society.

In fantasy, a character living in subterranean realms.

An inhabitant of the fictional world beneath Earth’s surface (e.g., "The Underland" in literature).

Relating to a subterranean or underground environment.

Pertaining to inhabitants of an underground society.

Describing something originating from below the surface.

Associated with lower levels in geographical contexts, like caves or tunnels.

Characterizing creatures that dwell beneath the earth's crust.