Word.ws English Dictionary

undersea

undersea adjective: existing, relating to, or made for use beneath the sea, that is, beneath the sea surface, inside the sea.

Adjective

undersea (not comparable)

  1. Existing, relating to, or made for use beneath the sea, that is, beneath the sea surface, inside the sea.
    • Near-synonym: underwater
    • It is not known just what action will be taken against the captain of the undersea boat.1920, George M. Battey, Jr., 70, 000 Miles on a Submarine Destroyer, Webb & Vary Company, page 133

Examples of undersea in a sentence

  • An undersea tunnel to the little island.1923, The Saturday Evening Post, G. Graham, page 58:
  • Sea Lab I, the Navy’s new undersea laboratory, complete with observation porch and garage, should become safe to operate at the 200 foot level.1966, Robert B. Thomas, The Old Farmer's Almanc, Yankee Pub, page 44:
  • In less than a decade, these otherworldly undersea landscapes, lush with life, have all but disappeared along 200 miles of coast north of San Francisco's Golden Gate Bridge.2022 April 30, David Helvarg, “Climate change threatens another California forest, this one underwater”, in The New York Times, New York...
  • The Channel Tunnel is the longest undersea tunnel in the world, with this section being 38km (23.6 miles) long.2022 December 28, “The essential Eurotunnel”, in RAIL, number 973, page 59:

All 13 example sentences with undersea

Synonyms of undersea

Origin of undersea

From under- + sea.

Questions about undersea

What does undersea mean?
Undersea means existing, relating to, or made for use beneath the sea, that is, beneath the sea surface, inside the sea.
How do you use undersea in a sentence?
An undersea tunnel to the little island.
What part of speech is undersea?
Undersea is an adjective.

Words near undersea in the dictionary

  1. underscreening
  2. underscribe
  3. underscribes
  4. underscrub
  5. underscrupulous
  6. undersea
  7. underseal
  8. undersealed
  9. undersealing
  10. underseals
  11. underseaman

Source and license

Adapted from Wiktionary: undersea (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Pronunciation audio from Wikimedia Commons, each file under its own free license: LL-Q1860 (eng)-Flame, not lame-undersea.wav.

Cite this entry: “undersea.” Word.ws, https://word.ws/undersea. Based on Wiktionary, CC BY-SA 4.0.