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Synonyms

undersea

American  
[uhn-der-see] / ˈʌn dərˌsi /

adjective

  1. located, carried on, or used under the surface of the sea.

    undersea life.

adverb

  1. underseas.

undersea British  
/ ˈʌndəˌsiː /

adjective

  1. below the surface of the sea

"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 undersea

First recorded in 1605–15; under- + sea

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.

Some of the crucial work done at Bell Labs might now seem mundane: for example, how to fabricate sheathing so undersea cables wouldn’t be chewed through by Toredo worms.

From The Wall Street Journal

"Sea mines and other explosive devices can cause acoustic disturbance impacting sea mammals and other animals, and blast damage to natural undersea structures such as reefs," Weir said.

From Barron's

As part of her training, she spent 18 days as an aquanaut living in an undersea habitat.

From BBC

Will he bow to US pressure to nix a project to link China and Chile across the Pacific via an undersea fiber optic cable?

From Barron's

The search for mines can include divers, unmanned undersea vehicles and specialized ships.

From The Wall Street Journal

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

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.