Hairs of eyebrow

Eyebrow hairs (also referred to as the supercilium) are the arch of terminal hair located on the brow — the soft tissue overlying the bony supraorbital ridge, at the junction of the frontalis and orbicularis oculi muscles. They are among the first visible terminal hairs to develop during embryogenesis and are present from birth onward.

The eyebrow is conventionally divided into three parts: medial, middle (central), and lateral. The hairs of the medial part are oriented laterally, while those of the middle part are oriented superolaterally. The transition between the middle and lateral parts is less frequently visible. Eyebrows typically extend further laterally than medially in relation to the eye and are wider and thicker medially.