figurative. Applied to the surface of the sea, a lake, a river, or the ground: with various associations from the literal sense.
The surface of the water. with the rim of: in the uppermost part of. Obsolete.
The upper edge or surface of water. archaic or poetic.
A plane or level corresponding to the upper surface of a body of water; a water surface; (Physical Geography) = water table, n. 4.