supercilium
/ˌsuːpəˈsɪlɪəm/ /ˌs(j)uːpəˈsɪlɪəm/noun
1Chiefly Anatomy. The eyebrow. Now rare.
2 Zoology. A superciliary marking or structure, especially in a bird.
3The narrow fillet above the cymatium of a cornice.
4A fillet above and below the scotia of an Attic base.
5The lintel or transverse part of a door frame.
6Superciliousness, haughtiness. Also: an instance of this, a supercilious demeanour. Now rare ( humorous in later use).
Origin
Late Middle English; earliest use found in John Trevisa (c1342–?1402), translator. From classical Latin supercilium eyebrow, haughtiness, overhanging edge, brow, small hillock, projection in a coastline, (in architecture) overhang, (in a door frame) lintel, in post-classical Latin also lip or margin of a bony cavity, probably from super- + cilium, although cilium is first attested later and may be derived from supercilium.