IPA: /ˈaɪʃaɪn/
KK: /ˈaɪˌʃaɪn/
The light that reflects off the eyes of certain animals when light shines on them in the dark.
At night, the eyeshine of the deer was visible in the headlights of the car.
Eyeshine is formed from "eye" (from Old English "eage", meaning the organ of sight) and "shine" (from Old English "scīnan", meaning to emit light). The word "eyeshine" refers to the reflection of light from the eyes, often seen in animals at night.
Think of the 'organ of sight' ('eye') reflecting 'light' ('shine') — that's what eyeshine means.