referring to the deep sea or abyss

an undersea elevation rising from the continental shelf

the measurement of depths of water in oceans, seas, and lakes

a small body of water set off from the main body; an inlet of the sea usually smaller than a gulf

near or on the bottom

a deep narrow valley with steep sides and often with a stream flowing through it

a point or extension of land jutting out into water as a peninsula or point

an old, wave-cut terrace gently sloping seaward

beyond the shelf, the slope descends more steeply into the ocean shelf

a stream of water smaller than a river, often a tributary to a river