Origin: Greek suffix -osis
Actinic keratosis has 2 different meanings across 1 category:
an overgrowth of skin layers resulting from extended exposure to the sun
A potentially precancerous skin lesion, typically on the upper portion of the head, characterized by discolored, thickened or scaly growths of keratin and caused by repeated exposure to ultraviolet light, such as from sunlight or tanning beds.