Photoresponsive

Part of speech: adjective

Definitions

1. Characterizing the behavior of materials or living organisms that adjust their properties when subjected to light stimuli
2. Referring to the capacity of certain substances or life forms to modify their characteristics in reaction to light exposure
3. Describes materials or organisms that change their properties upon exposure to light

Etymology: The word is a plain modern compound with no dramatic backstory, so its interest lies in the parts. The first part, "photo-", comes from the Ancient Greek "phôs" (genitive "phôtos"), meaning "light," which also gave us "phase" in its older sense of "appearance" or "aspect" and "phosphor," the glowing substance. Ancient Greek formed combining forms from it, such as "phōto-," which English later took up as a prefix for anything involving light or photography. The second part, "responsive," is an English adjective meaning "reacting readily to an influence or stimulus," built from "respond" plus "-ive." Joined to "photo-," the compound describes something that responds to light, and the word is used especially of materials whose properties shift when illuminated, as well as of organisms that react to light.

Synonyms: light-sensitive