retina

Meaning

Noun

• The thin layer of cells at the back of the eyeball that contains rods and cones sensitive to light, which trigger nerve impulses that pass via the optic nerve to the brain, where a visual image is formed.

Origin

• From Middle English rethina, borrowing from Medieval Latin rētīna ("relating to a net"), ellipsis of tunica rētīnus, used to describe the blood vessel system at the back of the eye. The phrase is attested in the 12th century in Guillelmus the abbot and Gerard of Cremona—the latter may have created this phrase as a translation for [[طَبَقَة شَبَكِيَّة "net-like layer", which translates ἀμφιβληστροειδής χῐτών.