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retinal

2
[ret-n-al, -awl]

noun Biochemistry.

an orange pigment, C20H28O, that is the active component of rhodopsin and is liberated upon the absorption of light in the vision cycle; vitamin A aldehyde.
Also ret·i·nene [ret-n-een] /ˈrɛt nˌin/.

Origin of retinal

2
First recorded in 1940–45; retin(a) + -al3
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for retinene

retinene

retinal (ˈrɛtɪnəl)

noun

the aldehyde form of the polyene retinol (vitamin A) that associates with the protein opsin to form the visual purple pigment rhodopsin

Word Origin for retinene

C20: from retina + -ene
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for retinene

retinal

adj.

1838; see retina + -al (1).

Online Etymology Dictionary, © 2010 Douglas Harper
retinene in Medicine

retinene

[rĕt′n-ēn′]

n.

Either of two yellow to red retinal pigments, formed by oxidation of vitamin A alcohols.

retinal

[rĕt′n-ăl′, -ôl′]

n.

retinaldehyde
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.