vellos

Vellos is the plural of vello in Spanish, typically referring to fine hairs on the body. In common usage, it denotes the pale, short hairs that cover much of the skin, especially on the arms, legs, and face, and contrasts with thicker, darker terminal hair. The term is also used in biology to describe this hair type.

Biologically, vellus hair is a type of hair that is short, soft, and lightly pigmented. It forms on most parts of the body during infancy and continues through adulthood in many areas. Vellus hairs are produced by specialized follicles and differ from terminal hairs, which are longer, coarser, and more pigmented.

Hair development involves a growth cycle with phases: anagen, catagen, and telogen. In puberty, hormonal changes can shift hair patterns, leading some vellus hairs to transition to terminal hair in regions such as the underarms and pubic area, and, in men, the face. Individual variation is common.

Vellus hair has clinical relevance in dermatology. Conditions such as hirsutism and alopecia can alter hair type and distribution. Cosmetic practices, including shaving, waxing, and laser hair removal, address visible hair but target terminal hair more than vellus hair. Lanugo, the fine fetal hair, is typically replaced by vellus hair before birth.