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Synonyms

deep-sea

American  
[deep-see] / ˈdipˈsi /

adjective

  1. of, pertaining to, in, or associated with the deeper parts of the sea.

    deep-sea fishing; deep-sea diver.


deep-sea British  

noun

  1. (modifier) of, found in, or characteristic of the deep parts of the sea

    deep-sea fishing

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of deep-sea

First recorded in 1620–30

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

“I’ve always been fascinated by deep-sea animals,” Pereira said.

From Los Angeles Times Sep. 5, 2026

Elements commonly associated with interstellar dust have been found in deep-sea sediment cores, Antarctic snow, and samples from the Moon that correspond to these time periods.

From Science Daily Sep. 2, 2026

Conservationists say this and other extraordinary deep-sea snails, limpets, mussels and clams could be threatened by plans to mine valuable minerals from the deep seabed.

From BBC Jul. 9, 2026

The agency approached Hughes, the aerospace businessman, to build a massive deep-sea drill-ship called the Hughes Glomar Explorer, and paid him more than $350 million—billions in today’s money.

From The Wall Street Journal Jun. 16, 2026

“Today is truly a momentous day,” the captain tells us, “for we shall test the diving bell and see if Caden’s knowledge of deep-sea exploration rings true.”

From "Challenger Deep" by Neal Shusterman

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