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
Jim Dobson, Forbes.com, 4 Aug. 2025
There were dense beds of clams, each up to 9 inches long, and snow-like microbial mats creating an ethereal undersea dusting, dozens of feet wide.
—Jackson Peck, NBC news, 31 July 2025
Most Pacific Rim nations have advanced warning systems and shelter routines, and Japan in particular now has a widespread undersea detection system for seismic activity.
—Tom Chivers, semafor.com, 30 July 2025
This past spring, the importance of the station became clear when a massive slab of sea ice sliced through an undersea fiber-optic cable, cutting off internet to communities across the North Slope region.
—Nayeli Jaramillo-Plata, CNN Money, 29 July 2025
See All Example Sentences for undersea
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Adjective
Lindblad joined forces with National Geographic in 2004 providing guests with unique experiences, including immersive programs for photographers, young explorers and undersea enthusiasts, as well as opportunities to explore alongside the National Geographic Experts who join select voyages.
—Jim Dobson, Forbes.com, 4 Aug. 2025
There were dense beds of clams, each up to 9 inches long, and snow-like microbial mats creating an ethereal undersea dusting, dozens of feet wide.
—Jackson Peck, NBC news, 31 July 2025
Most Pacific Rim nations have advanced warning systems and shelter routines, and Japan in particular now has a widespread undersea detection system for seismic activity.
—Tom Chivers, semafor.com, 30 July 2025
This past spring, the importance of the station became clear when a massive slab of sea ice sliced through an undersea fiber-optic cable, cutting off internet to communities across the North Slope region.
—Nayeli Jaramillo-Plata, CNN Money, 29 July 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 Aug. 2025.
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