Definition from Wiktionary, the free dictionary
subsurface (plural subsurfaces)
- Something that is below the layer that is on the surface.
- Before we could lay the flooring we had to lay a subsurface under it to keep it flat and support it.
- (countable, mathematics) A surface which is a submanifold of another surface.
a surface which is a submanifold of another surface
subsurface (not comparable)
- below the surface
- variations in subsurface conditions
- subsurfacely, below the surface