Iodopsins

Part of speech: noun

Definitions

1. Photosensitive proteins found in the retinal cones that enable color vision and are sensitive to different wavelengths of light
2. A type of photoreceptor molecule located in the cone cells of the eyes that play a role in perceiving colors under light exposure
3. Biochemical compounds that contribute to the detection of color in bright light conditions by acting in conjunction with other visual photoreceptors

Etymology: "Iodopsins" is simply the plural of "iodopsin", so the noun it names is the one that matters here. The "-opsin" ending comes from Greek "ops" (eye, sight), the same root behind "optic" and "-opsis" in words for vision. Opsins are the light-sensitive proteins found in the retina, and the "iod-" element points to iodine: the compounds were named for their chemistry, since they are built around a retinal molecule whose structure contains iodine-derived sensitivity to bright light. The name therefore combines a chemical prefix with a Greek word for sight, a common pattern in modern biochemistry where older Greek roots are recombined to label newly discovered molecules.