deep-sea /ˈdipˈsi/
  (a.)深海的,遠洋的
  Deep-sea a. Of or pertaining to the deeper parts of the sea; as, a deep-sea line (i. e., a line to take soundings at a great depth); deep-sea lead; deep-sea soundings, explorations, etc.
  ◄ ►
  deep-sea
       adj : of or taking place in the deeper parts of the sea; "deep-sea
             fishing"; "deep-sea exploration"