Chalazion

A chalazion is an inflammatory lump or cyst on the eyelid caused by the blockage of an oil gland in the eyelid. Both your upper and lower eyelids may be affected and you can have more than one lesion.

They are more common if you have an eye condition called blepharitis or if you have eczema. A chalazion is not a stye, which is an infection at the base of an eyelash.