vellus hair

noun

vel·​lus hair ˈvel-əs- 

: a short, fine, light-colored body hair that is found on most surfaces of the body and in which the hair shaft lacks the central inner layer found in a terminal hair

The transformation of small, fine and unpigmented vellus hair follicles to terminal hair follicles, which are longer, thicker and more pigmented, is stimulated by androgens.

—Aurora Guerra-Tapia et al., American Journal of Clinical Dermatology

Terminal hairs are larger in diameter, with their bulb extending down to the subcutaneous fat, while vellus hairs are much smaller, with their bulb located in the mid dermis.

—Primary Care Reports