Synonyms: subsurface
Definition: beneath the surface
Usage: subsurface materials of the moon
Similar words: underground, belowground
Definition: under the level of the ground
Usage: belowground storage areas; underground caverns
Similar words: undersea, submarine
Definition: beneath the surface of the sea
Similar words: submerged, submersed, underwater
Definition: beneath the surface of the water
Usage: submerged rocks
Similar words: subterranean, subterraneous
Definition: being or operating under the surface of the earth
Usage: subterranean passages; a subsurface flow of water