Definition

Noun: A condition characterized by the localized or widespread loss of pigment (color) in the hair, resulting in white or gray strands or patches. It specifically refers to the whitening or graying of hair due to the absence of melanin.

Usage

Poliosis is a medical term used to describe the depigmentation of hair. It can occur in small, isolated patches or affect larger areas. It is often associated with various genetic, autoimmune, or inflammatory conditions.

Examples

• The most distinctive feature of the syndrome is a white forelock, a form of poliosis present from birth.
• The dermatologist noted a patch of poliosis in the patient's eyebrow, which had developed recently.
• Poliosis can sometimes be the first noticeable sign of an underlying condition like vitiligo or alopecia areata.

Advanced Usage

• "Poliosis circumscripta": A specific term sometimes used for a well-defined, isolated patch of white hair.
• The condition is often discussed in dermatological contexts concerning differential diagnosis, as poliosis itself is a symptom rather than a disease.

Variants and Related Words

• Canities: A more general term for the graying of hair, typically due to aging. Poliosis is a specific type of canities that is often premature and patchy.
• Leukotrichia: A synonymous term for poliosis, also meaning local whitening of the hair.

Synonyms

• Leukotrichia
• Localized canities
• Hair depigmentation

Antonyms

• (Conceptually) Pigmented hair; Melanated hair.

Notes

Poliosis is distinct from general graying of hair due to aging. It is a clinical sign that may prompt investigation for associated syndromes or autoimmune disorders.

Noun

1. loss of color from the hair