velluskarva

Velluskarva refers to the fine, short, and usually unpigmented hairs that cover much of the human body. In medical and anatomical terminology, these hairs are called vellus hair, and they differ from terminal hairs, which are thicker, longer, and pigmented. Vellus hair originates from miniaturized hair follicles with a brief or negligible anagen (growth) phase, resulting in a hair shaft that is often barely visible to the naked eye.

Distribution and development vary with age, sex, and hormonal factors. At birth and during childhood, vellus hair is widely present on most of the body's surface, including the limbs and trunk. During puberty, and under the influence of androgens in certain regions, some vellus hairs can transition into terminal hair, especially in androgen-sensitive areas. Other vellushairs may remain fine and inconspicuous throughout life.

Clinical relevance can arise from changes in hair growth patterns. In androgenetic alopecia, for example, terminal hairs in affected regions may gradually miniaturize into thinner, vellus-like hairs, contributing to visible hair thinning. Conversely, conditions such as hirsutism or certain medications can alter the balance between vellus and terminal hair, leading to increased growth of thicker hair in unusual areas. Regrowth after scalp injuries or diseases can also initially present as vellus hairs before maturing into terminal hairs.

Functionally, the precise role of vellus hair is not fully understood, but these hairs are thought to contribute to minor protective and regulatory functions, including reducing friction and possibly participating in subtle thermoregulation.