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definitions

retinal

1
[ret-n-uh l]
adjective
  1. of or relating to the retina of the eye.

Origin of retinal

1
First recorded in 1830–40; retin(a) + -al1

retinal

2
[ret-n-al, -awl]
noun Biochemistry.
  1. 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. 2018

Examples from the Web for retinal

Contemporary Examples of retinal

Historical Examples of retinal

  • Mike the Angel put his face in the rest for the retinal photos.

    Unwise Child

    Gordon Randall Garrett

  • “Such as fingerprint and retinal patterns,” said Lieutenant Nariaki.

    Unwise Child

    Gordon Randall Garrett

  • Retinal pattern 490-BJ4-67—which is also the code that is supposed to get me through your blockade.

    Planet of the Damned

    Harry Harrison

  • This is generally accounted for by fatigue of the retinal process.

    Visual Illusions

    Matthew Luckiesh

  • The retinal image of the object is not only vague, but also distorted.

    Clever Hans

    Oskar Pfungst

Word Origin and History for retinal
adj.

1838; see retina + -al (1).

Online Etymology Dictionary, © 2010 Douglas Harper
retinal in Medicine

retinal

[rĕt′n-ăl′, -ôl′]
n.
  1. retinaldehyde
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.