supercilium

thumb|right|upright|The whinchat has a prominent white supercilium.

The supercilium is a plumage feature found on the heads of some bird species. It is a stripe that runs from the base of the bird's beak above its eye, finishing somewhere towards the rear of the bird's head. Also known as an "eyebrow", it is distinct from the eyestripe, which is a line that runs across the lores, and continues behind the eye. Where a stripe is present only above the lores, and does not continue behind the eye, it is called a supraloral stripe or simply supraloral. On most species that display a supercilium, it is paler than the adjacent feather tracts.