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
Kaif Shaikh, Interesting Engineering, 11 Sep. 2025
Off the shores of the island lie rainbow coral reefs, seagrass beds, and undersea ridges sheltering hundreds of species of fish, dugongs, and 15 species of dolphins and whales.
—M. Rajshekhar, Time, 11 Sep. 2025
Australia—a key United States ally in the South Pacific—is expanding its drone fleet for undersea and aerial warfare after China unveiled its unmanned weapon systems.
—Ryan Chan, MSNBC Newsweek, 10 Sep. 2025
Damage to two major undersea cables off the coast of Jeddah over the weekend slowed the internet in the UAE and as far away as India and Pakistan, according to monitoring firm NetBlocks.
—Kelsey Warner, semafor.com, 8 Sep. 2025
See All Example Sentences for undersea
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Adjective
Secret undersea freshwater aquifers This year’s offshore drilling campaign off New England didn’t just infer freshwater under the Atlantic seafloor.
—Kaif Shaikh, Interesting Engineering, 11 Sep. 2025
Off the shores of the island lie rainbow coral reefs, seagrass beds, and undersea ridges sheltering hundreds of species of fish, dugongs, and 15 species of dolphins and whales.
—M. Rajshekhar, Time, 11 Sep. 2025
Australia—a key United States ally in the South Pacific—is expanding its drone fleet for undersea and aerial warfare after China unveiled its unmanned weapon systems.
—Ryan Chan, MSNBC Newsweek, 10 Sep. 2025
Damage to two major undersea cables off the coast of Jeddah over the weekend slowed the internet in the UAE and as far away as India and Pakistan, according to monitoring firm NetBlocks.
—Kelsey Warner, semafor.com, 8 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 16 Sep. 2025.
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