You searched for: “photopathy
photopathy (s) (noun), photopathies (pl)
1. A pathological effect caused by light: A form of photopathy can occur when a person hikes in a region of glaciers on a sunny day and doesn't wear any sunglasses!
2. The influence of light upon organisms: Photopathy can relate to life forms that migrate from an area of greater light (positive photopathy) to one with less intensity of light (negative photopathy).
3. Any abnormal change in the skin induced by light: When Bob was out doing gardening, he always wore a shirt or jacket with long sleeves in order to protect his arms from any photopathies that might affect his skin.