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
Melanie Hicken, CNN Money, 24 Oct. 2025
Western officials, while refraining from discussing operational details, have stressed their commitment to defending critical undersea infrastructure and monitoring sites with strategic vulnerabilities.
—Jordan King, MSNBC Newsweek, 24 Oct. 2025
Experts say Harmony could reshape undersea dynamics in the Arctic, where US and NATO submarines have long enjoyed stealth advantages.
—Kapil Kajal, Interesting Engineering, 24 Oct. 2025
Construction of an undersea tunnel in the Bering Strait would require Musk's Boring Company to work through below-freezing temperatures in a region without existing infrastructure and with deep and frequent earthquakes.
—Lora Kolodny, CNBC, 17 Oct. 2025
See All Example Sentences for undersea
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Adjective
Konstantin Sokolov is the founder of a private equity firm focused on tech, finance and infrastructure, a major shareholder in Armenia’s largest telecom company and the chairman of an undersea cable initiative to carry energy and telecommunications between Africa and Europe.
—Melanie Hicken, CNN Money, 24 Oct. 2025
Western officials, while refraining from discussing operational details, have stressed their commitment to defending critical undersea infrastructure and monitoring sites with strategic vulnerabilities.
—Jordan King, MSNBC Newsweek, 24 Oct. 2025
Experts say Harmony could reshape undersea dynamics in the Arctic, where US and NATO submarines have long enjoyed stealth advantages.
—Kapil Kajal, Interesting Engineering, 24 Oct. 2025
Construction of an undersea tunnel in the Bering Strait would require Musk's Boring Company to work through below-freezing temperatures in a region without existing infrastructure and with deep and frequent earthquakes.
—Lora Kolodny, CNBC, 17 Oct. 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 7 Nov. 2025.
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