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
Jason Ma, Fortune, 4 Oct. 2025
The United States must lean into this undersea advantage and prioritize maintaining it.
—Seth G. Jones, Foreign Affairs, 26 Sep. 2025
An undersea submersible has revealed crabs, worms, and fish living on World War II explosives in the Baltic Sea.
—Sujita Sinha, Interesting Engineering, 26 Sep. 2025
Rozwadowski analyzes his 1957 novel The Deep Range, in which a former astronaut takes a job on an undersea ranch.
—Danny Robb, JSTOR Daily, 26 Sep. 2025
See All Example Sentences for undersea
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Adjective
European officials have also been warning about other hybrid threats and suspect Moscow was behind a string of incidents, including the sabotage of an undersea cable, cyberattacks, GPS jamming of civil aviation, and even acts of arson.
—Jason Ma, Fortune, 4 Oct. 2025
The United States must lean into this undersea advantage and prioritize maintaining it.
—Seth G. Jones, Foreign Affairs, 26 Sep. 2025
An undersea submersible has revealed crabs, worms, and fish living on World War II explosives in the Baltic Sea.
—Sujita Sinha, Interesting Engineering, 26 Sep. 2025
Rozwadowski analyzes his 1957 novel The Deep Range, in which a former astronaut takes a job on an undersea ranch.
—Danny Robb, JSTOR Daily, 26 Sep. 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 12 Oct. 2025.
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