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
Yohann Ripert, The Orlando Sentinel, 10 July 2025
The warm shallow waters off the Dry Tortugas a draw for snorkelers of all ages while nearby John Pennekamp Coral Reef State Park, the first undersea park in the US, is great for viewing the various coral species, plus turtles, parrot fish and butterfly fish.
—Brittany Anas, Forbes.com, 3 July 2025
Related article Ships, sea drones and AI: How NATO is hardening its defense of critical Baltic undersea cables
CNN was not able to locate the registered owner of the Jaguar for comment.
—Joseph Ataman, CNN Money, 20 May 2025
Crossing over polar regions shortens the distances that cargo vessels, airplanes, undersea cables, or intercontinental ballistic missiles must travel to reach their destinations.
—Michael Albertus, Foreign Affairs, 24 June 2025
See All Example Sentences for undersea
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Adjective
From undersea cables and critical minerals to port security and immigration flows, what happens in Africa is already shaping debates from Capitol Hill to communities across Florida.
—Yohann Ripert, The Orlando Sentinel, 10 July 2025
The warm shallow waters off the Dry Tortugas a draw for snorkelers of all ages while nearby John Pennekamp Coral Reef State Park, the first undersea park in the US, is great for viewing the various coral species, plus turtles, parrot fish and butterfly fish.
—Brittany Anas, Forbes.com, 3 July 2025
Related article Ships, sea drones and AI: How NATO is hardening its defense of critical Baltic undersea cables
CNN was not able to locate the registered owner of the Jaguar for comment.
—Joseph Ataman, CNN Money, 20 May 2025
Crossing over polar regions shortens the distances that cargo vessels, airplanes, undersea cables, or intercontinental ballistic missiles must travel to reach their destinations.
—Michael Albertus, Foreign Affairs, 24 June 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 24 Jul. 2025.
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