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
The Editors, JSTOR Daily, 19 Sep. 2025
Tsunamis are a series of giant waves caused by undersea earthquakes at tectonic plate boundaries, or volcanic eruptions.
—George Petras, USA Today, 18 Sep. 2025
MacVean rose up the ranks, eventually becoming executive officer of the USS Parche (SSN-683), which became famous in the Silent Service for tapping Soviet undersea communication cables and recovering Soviet missile fragments.
—Gary Robbins, San Diego Union-Tribune, 16 Sep. 2025
Flynn then learns all about marine life, including coral reefs and mangrove forests, undersea mountain ranges and even giant squid, as well as how precious — and how endangered — the oceans are.
—Gillian Telling, PEOPLE, 16 Sep. 2025
See All Example Sentences for undersea
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Adjective
For the less adventurous, glass-bottom boats also offer a view of the undersea installation.
—The Editors, JSTOR Daily, 19 Sep. 2025
Tsunamis are a series of giant waves caused by undersea earthquakes at tectonic plate boundaries, or volcanic eruptions.
—George Petras, USA Today, 18 Sep. 2025
MacVean rose up the ranks, eventually becoming executive officer of the USS Parche (SSN-683), which became famous in the Silent Service for tapping Soviet undersea communication cables and recovering Soviet missile fragments.
—Gary Robbins, San Diego Union-Tribune, 16 Sep. 2025
Flynn then learns all about marine life, including coral reefs and mangrove forests, undersea mountain ranges and even giant squid, as well as how precious — and how endangered — the oceans are.
—Gillian Telling, PEOPLE, 16 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 24 Sep. 2025.
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