the zone of the sea, extending from low-water mark to a depth of ninety feet, in which seaweeds of the genus Laminaria are found.

Oceanography. The bottom layer of the ocean, in which (by analogy with the original meaning of sense 2a) there is little temperature variation with…

Oceanography. The upper layer of the ocean in which the water temperature rapidly decreases as depth increases.

(Oceanogr.), any of a number of layers in the sea which give rise to strong acoustic echoes owing to the presence of a high concentration of living…

a layer of water in which sound is propagated over long distances with minimum energy loss, usually because of refraction back into this layer from…

The colder, deeper part of the oceans. Contrasted with thermosphere.

The warmer, upper part of the oceans.

Used attributively to designate concepts and phenomena associated with the work of V. W. Ekman. Ekman current meter n. a device for measuring the…

a narrow layer of water separating layers of differing temperature and salinity.

Oceanography and Limnol. Of sea or lake water: turbid. Chiefly in nepheloid layer n. a layer of water, typically near the bottom, containing…