subterranean

subterranean

subterranean

CEFR: C1-C2 /sub-ter-ranean/ [s.ah0.b.t.er0.ey1.n.iy0.ah0.n]

The adjective "subterranean" describes something that is under the ground or below the surface of the earth. For example:

Example Sentences:
A subterranean river or tunnel is under the ground.
The Japanese Gardens' coral reef, situated in the western tip of the Arabian Peninsula, is considered one of the most beautiful reefs on earth, contains many fish which are indigenous to it, and exhibits a unique construction of the subterranean landscape.