mesopelagic

American  

[mez-uh-puh-laj-ik, mes-, mee-zuh-, -suh-] / ˌmɛz ə pəˈlædʒ ɪk, ˌmɛs-, ˌmi zə-, -sə- /

adjective

Oceanography.

1. of, relating to, or living in the ocean at a depth of between 600 feet (180 meters) and 3,000 feet (900 meters).

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mesopelagic British  

/ ˌmɛsəʊpəˈlædʒɪk /

adjective

1. of, relating to, or inhabiting the intermediate depths of the ocean between approximately 100 and 1000 metres

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Etymology

Origin of mesopelagic

First recorded in 1945–50; meso- + pelagic

Example Sentences

See Examples For:

mesopelagic

"These mesopelagic fish are doing the hard work of connecting the deep ocean to the surface food web. If we don't understand them, we're basically trying to solve a puzzle with the middle pieces missing."

From Science Daily ● Dec. 28, 2025

Also known as the mesopelagic, it makes up a fifth of the ocean’s total volume, and much of it remains largely unexplored.

From National Geographic ● Feb. 13, 2024

Superflex chose to highlight the siphonophore as a representative of the mesopelagic zone of the sea, known as the twilight zone, which receives little to no sunlight.

From New York Times ● Sep. 14, 2021

This dive will take place at night, when fish living in the deep ocean do their daily vertical migration to the mid-ocean, or mesopelagic zone, about 300 meters deep.

From Scientific American ● Mar. 3, 2014

In the middle depths of the ocean—the mesopelagic zone that is located 200 to 1000 meters below the surface—the vast majority of organisms can bioluminesce.

From Science Magazine ● Sep. 7, 2012