photic zone

American  

noun

Biology.

1. the upper layer of a body of water delineated by the depth to which enough sunlight can penetrate to permit photosynthesis.

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Etymology

Origin of photic zone

First recorded in 1970–75

Example Sentences

Footage from remotely operated submersibles exploring seafloors far below the photic zone revealed that microbial mats can develop there as well, but they are produced by chemosynthetic bacteria.

From Science Daily • Mar. 8, 2026

The region starts about 1,000 feet down — just beneath the photic zone, which gets enough sunlight to support photosynthesis and most of the sea’s plants — and descends for miles.

From New York Times • May 30, 2024

Describe the differences in the abiotic factors of the open ocean photic zone compared to the open ocean aphotic zone.

From Textbooks • Jan. 1, 2018

Below the photic zone is the dark aphotic zone, where photosynthesis cannot occur.

From Textbooks • Jan. 1, 2018

Coral reefs are ocean ridges formed by marine invertebrates living in warm shallow waters within the photic zone of the ocean.

From Textbooks • Jan. 1, 2015