Cilium is a type of microscopic HAIR-like structure found on the surface of some cells. It is also known as a cilium or flagellum. The term cilium is derived from the Latin word for 'EYELASH'. HAIR is a four letter word meaning a threadlike outgrowth of the epidermis of an animal or human, LASH is a four letter word meaning to move with a sudden or forceful motion, EYELASH is a seven letter word meaning a short curved HAIR growing from the edge of the eyelid, and STYE is a four letter word meaning an inflamed swelling on the edge of the eyelid.