deep-sea

/D IY1 P S IY1/
adjective
  1. 1

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

  2. 2

    (sport fishing) of or related to open sea

    โ€œdeep-sea fishingโ€

  3. 3

    (of a port) able to accommodate the largest ships.

Source: https://en.wiktionary.org/wiki/deep-sea