An Etymological Dictionary of Astronomy and Astrophysics

Vision that occurs when the eye is dark-adapted. In scotopic vision, the level of luminance is so low that the retinal cones are not
stimulated, and there is no color vision. Same as scotopia; → dark adaptation.

Etymology (EN): Scotopic, from L. Gk. skoto- combining form of skotos “darkness” + -opia akin to ope “view, look,” ops “eye, face;” → vision.

Etymology (PE): Did, → vision; târiki noun from târik “dark,” Mid.Pers. târig “dark,” târ “darkness,” Av. taθra- “darkness,” taθrya- “dark,” cf. Skt. támisrâ- “darkness, dark night,” L. tenebrae “darkness,” Hittite taš(u)uant- “blind,” O.H.G. demar “twilight.”