un·der·sea
ˌən-dər-ˈsē 
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
Examples of undersea in a Sentence
Adjective
They are conducting undersea research.
Recent Examples on the Web
Julian Sancton, HollywoodReporter, 20 Jan. 2026
In late December, Finnish police detained a cargo vessel, the Fitburg, which was sailing from St Petersburg to Haifa in Israel, and was accused of damaging an undersea telecoms cable in the Baltic by dragging its anchor over it.
—The Week Uk, TheWeek, 18 Jan. 2026
The high seas also include extraordinary undersea landscapes such as submarine mountains and deep-sea trenches.
—Veronika Meduna, Forbes.com, 17 Jan. 2026
Finland has detained a ship and its crew after a critical undersea telecommunication cable connecting the country to Estonia was damaged Wednesday, Finnish authorities said.
—Ivana Kottasová, CNN Money, 31 Dec. 2025
See All Example Sentences for undersea
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Adjective
Young Roger Dooley was particularly enamored with the new hit series Sea Hunt, starring Lloyd Bridges as a former Navy frogman who solves undersea crimes.
—Julian Sancton, HollywoodReporter, 20 Jan. 2026
In late December, Finnish police detained a cargo vessel, the Fitburg, which was sailing from St Petersburg to Haifa in Israel, and was accused of damaging an undersea telecoms cable in the Baltic by dragging its anchor over it.
—The Week Uk, TheWeek, 18 Jan. 2026
The high seas also include extraordinary undersea landscapes such as submarine mountains and deep-sea trenches.
—Veronika Meduna, Forbes.com, 17 Jan. 2026
Finland has detained a ship and its crew after a critical undersea telecommunication cable connecting the country to Estonia was damaged Wednesday, Finnish authorities said.
—Ivana Kottasová, CNN Money, 31 Dec. 2025
See All Example Sentences for undersea
Cite this Entry
“Undersea.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undersea. Accessed 27 Jan. 2026.
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