system - a group of physiologically or anatomically related organs or parts; "the body has a system of organs for digestion"

cutis, skin, tegument - a natural protective covering of the body; site of the sense of touch; "your skin is the largest organ of your body"

hair - dense growth of hairs covering the body or parts of it (as on the human head); helps prevent heat loss; "he combed his hair"

glandulae sebaceae, sebaceous follicle, sebaceous gland - a cutaneous gland that secretes sebum (usually into a hair follicle) for lubricating hair and skin

nail - horny plate covering and protecting part of the dorsal surface of the digits