un·​der·​sea | \ ˌən-dər-ˈsē How to pronounce undersea (audio) \

Definition of undersea

 (Entry 1 of 2)

1 : being or carried on under the sea or under the surface of the sea undersea oil deposits undersea fighting
2 : designed for use under the surface of the sea an undersea fleet


\ ˌən-dər-ˈsēz How to pronounce undersea (audio) \
variants: or underseas

Definition of undersea (Entry 2 of 2)

: under the sea : beneath the surface of the sea photographs taken undersea

Examples of undersea in a Sentence


They are conducting undersea research.

Recent Examples on the Web: Adjective

But in the studio's new live-action remake of the 1989 movie, the rebellious undersea princess will depart from her classic appearance. oregonlive.com, "Disney network slaps back at notion Ariel has to be a white, blue-eyed redhead," 9 July 2019 As Disney preps its live action version of the undersea tale, there's a lot of buzz about the cast. Justin Kroll, chicagotribune.com, "Melissa McCarthy in talks to play Ursula in live-action ‘Little Mermaid’," 28 June 2019 Instead of spending time and money establishing a broadband connection using undersea wires, this plan has proven more effective for Arranmore. Currie Engel, Time, "This Remote Irish Island Is Hoping To Lure New Residents," 14 June 2019 Nautilus expeditions were shared with the world live, revealing the wonders of the undersea world in real time, in an effort to maximize the scientific outputs of expeditions and engage and inspire a new generation of young explorers. National Geographic, "Engineering and Robotics High School Workshop on the MIT Campus," 12 June 2019 New Zealand gained undersea territory six times larger than its terrestrial area. Richard Kemeny, Science | AAAS, "As countries battle for control of North Pole, science is the ultimate winner," 20 June 2019 An undersea earthquake had struck just off the coast and triggered a destructive tsunami, which hit shorelines all along the Indian Ocean as far away as Somalia. Megan Gannon, National Geographic, "How a 'forgotten' 600-year-old tsunami changed history," 27 May 2019 This Monday, it was revealed that Huawei is selling off its undersea cable business, which analysts interpreted as being at least partially motivated by the increasing toxicity of the Huawei brand. Vlad Savov, The Verge, "Huawei will build 5G network for Russia’s biggest carrier," 6 June 2019 Other undersea crops being grown in Alaska include urchins, sea cucumbers, mussels and giant geoduck clams. Anchorage Daily News, "Alaska’s fledgling mariculture industry expands its reach; former Dunleavy staffer named to fish board," 5 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'undersea.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of undersea


1613, in the meaning defined at sense 1


1645, in the meaning defined above

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Statistics for undersea

Last Updated

13 Jul 2019

Look-up Popularity

Time Traveler for undersea

The first known use of undersea was in 1613

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English Language Learners Definition of undersea

: found, done, or used below the surface of the sea


un·​der·​sea | \ ˈən-dər-ˈsē How to pronounce undersea (audio) \

Kids Definition of undersea

1 : being or done under the sea or under the surface of the sea an undersea volcano
2 : used under the surface of the sea an undersea vessel

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More from Merriam-Webster on undersea

Rhyming Dictionary: Words that rhyme with undersea

Spanish Central: Translation of undersea

Nglish: Translation of undersea for Spanish Speakers

Comments on undersea

What made you want to look up undersea? Please tell us where you read or heard it (including the quote, if possible).


something desired as essential

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