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
Condé Nast Traveler, 28 Mar. 2026
In a bid to redefine undersea engagement, scientists demonstrated the ability to ignite rocket systems at extreme depths.
—Mrigakshi Dixit, Interesting Engineering, 25 Mar. 2026
The modular design allows for three standard payload modules to be installed or one extra-large module, enabling missions such as Intelligence, Surveillance, and Reconnaissance (ISR), mine countermeasures, anti-submarine warfare, and undersea cable and pipeline inspection.
—David Szondy
march 22, New Atlas, 22 Mar. 2026
Now campaigners are pushing for the island’s ageing ferries to be replaced with undersea tunnels.
—The Week Uk, TheWeek, 20 Mar. 2026
See All Example Sentences for undersea
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Adjective
Sun-chasers need not look far to christen their own spot on the shore, while divers plumb the depths to investigate a multitude of undersea wonders in this world-class diving destination.
—Condé Nast Traveler, 28 Mar. 2026
In a bid to redefine undersea engagement, scientists demonstrated the ability to ignite rocket systems at extreme depths.
—Mrigakshi Dixit, Interesting Engineering, 25 Mar. 2026
The modular design allows for three standard payload modules to be installed or one extra-large module, enabling missions such as Intelligence, Surveillance, and Reconnaissance (ISR), mine countermeasures, anti-submarine warfare, and undersea cable and pipeline inspection.
—David Szondy
march 22, New Atlas, 22 Mar. 2026
Now campaigners are pushing for the island’s ageing ferries to be replaced with undersea tunnels.
—The Week Uk, TheWeek, 20 Mar. 2026
See All Example Sentences for undersea
Cite this Entry
“Undersea.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undersea. Accessed 3 Apr. 2026.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
