rho·​dop·​sin | \ rō-ˈdäp-sən \

Definition of rhodopsin

: a red photosensitive pigment in the retinal rods of the eye of most vertebrates that is important in vision in dim light

called also visual purple

Examples of rhodopsin in a Sentence

Recent Examples on the Web

Some use chlorophyll to convert sunlight during photosynthesis and others use rhodopsins, proteins that bind to a form of vitamin A called retina to capture light. Shandria Sutton, Science | AAAS, "New ‘light-eating’ protein discovered in the Sea of Galilee," 5 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rhodopsin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of rhodopsin

1878, in the meaning defined above

History and Etymology for rhodopsin

International Scientific Vocabulary rhod- + Greek opsis sight, vision + International Scientific Vocabulary -in entry 1 — more at optic

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Time Traveler for rhodopsin

The first known use of rhodopsin was in 1878

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More Definitions for rhodopsin


rho·​dop·​sin | \ rō-ˈdäp-sən \

Medical Definition of rhodopsin

: a red photosensitive pigment in the retinal rods of marine fishes and most higher vertebrates that is important in vision in dim light, is quickly bleached by light to a mixture of opsin and retinal, and is regenerated in the dark

called also visual purple

More from Merriam-Webster on rhodopsin

Britannica.com: Encyclopedia article about rhodopsin

Comments on rhodopsin

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