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.

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

In April 2022, the senior military officers say, they approached her through a member of their unit who was a hobby deep-sea diver.

From The Wall Street Journal • Jun. 12, 2026

It was known that when whales die and drop to the seafloor, their sunken bodies -- called "whale falls" -- provide a source of food to deep-sea creatures.

From Barron's • Jun. 10, 2026

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

From BBC • May 21, 2026

Basically it looked like a chair on a deep-sea boat, that you would sit in if you wanted to hunt shark or marlin or sea monsters.

From "The Last Olympian" by Rick Riordan

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