deep-sea

Of, related to or located in the deeper part of the sea.

The oarfish is a deep-sea fish.

of or taking place in the deeper parts of the sea

Of or related to an open sea.

deep-sea fishing

глубоково́дныйglubokovódnyj, глубоково́дныйglubokovódnyj

Of a port, able to accommodate the largest ships.