Syllable division and stress derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
deep-sea is an adjective meaning "of or taking place in the deeper parts of the sea". It carries one recorded sense.
of or taking place in the deeper parts of the sea
“deep-sea fishing”
“deep-sea exploration”
Definitions, synonyms and semantic relations for deep-sea come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. .