Source : Webster's Revised Unabridged Dictionary (1913)

Supercilium \Su`per*cil"i*um\, n. [L.] (Zo["o]l.)
   The eyebrow, or the region of the eyebrows.

Source : WordNet®

supercilium
     n : the arch of hair above each eye [syn: {eyebrow}, {brow}]