Eyeshine (noun) is the reflection of light from the inner surface of the eye through the pupil, giving the eye a luminous appearance, especially in cats. This is an affect of something called the tapetum lucidum (meaning "bright tapestry" in the Latin), which is a layer of tissue found directly behind or sometimes within the retina. Humans do not have eyeshine. But wouldn't it be super creepy if they did? So here's your warning - if when out in this most haunted of seasons trick-or-treating or wandering a cornfield and you happen to spot a human with glowing eyes... it's probably not human. Run!
