of or relating to the biogeographic region of the ocean bottom between the littoral and bathyal zones, from the low water line to the edge of the continental shelf, or to a depth of approximately 660 feet (200 meters).
being or situated in the zone of a lake extending from the lowest depth of rooted photosynthetic plants to the level at which the photosynthetic rate of flora equals the respiration rate.
Relating to the region of the ocean bottom between the low tide line and the edge of the continental shelf, ranging in depth to about 200 m (656 ft). Unlike areas of the littoral zone, the sublittoral zone is always submerged. Compare littoral.
Relating to the deeper part of a lake below the area in which rooted plants grow.