Inner most layer of the hair that is composed of round cells; often absent in fine and naturally blond hair.

Autoimmune disorder that causes the affected hair follicles to be mistakenly attacked by a person's own immune system.

Boil; acute, localized bacterial infection of the hair follicle that produces constant pain.

The small, involuntary muscle in the base of the hair follicle.

Sever case of dandruff characterized by an accumulation of greasy or waxy scales mixed with sebum that stick to the scalp in crusts.

The part of the hair located below the surface of the epidermis.

Inflammation of the subcutaneous tissue caused by staphylococci.

Scientific study of hair and its diseases and care.

Long, coarse pigmented hair found on the scalp, legs, arms and bodies of males and females.

Process by which newly formed cells in the hair bulb mature, fill with keratin, move upward, lose their nucleus and die.

A weak, physical, cross-link side bond between adjacent polypeptide chains.

A condition of abnormal growth of hair, characterized by the growth of terminal hair in areas of the body that normally grow only vellus hair.