Synonyms

deep-sea

American

[deep-see] / ˈdipˈsi /

adjective

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

deep-sea fishing; deep-sea diver.

deep-sea British

noun

(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.

After returning to the Galápagos, the researchers brought dozens of deep-sea specimens to the Charles Darwin Research Station for examination.

From Science Daily • May 25, 2026

The black box was found after months of deep-sea searches in 2011.

From BBC • May 21, 2026

About a decade ago, Japan discovered a large, deep-sea rare earth deposit that is considered the world’s third-largest high-quality, mineral-rich rare earth reserve.

From Barron's • May 20, 2026

"But this turned into a special case that required focused efforts and expertise of several different individuals. This was a complex mystery that required morphological, genetic, deep-sea and bioinformatics expertise to solve."

From Science Daily • Apr. 27, 2026

Abbey and I hid nearby, on one of the deep-sea charter boats.

From "Flush" by Carl Hiaasen

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023