skullcap

Etymology

skull + cap

noun

1. A small domed cap that covers the area from the forehead to just above the back of the neck.
   He was a short man with a long hooked nose. A blue skull-cap with a red border scarcely covered his head of bristly grey hair, and a short-bodied but long Ringerike coat of dark grey frieze with worn velvet borders served to make the roundness and crookedness of his back still more conspicuous. 1886, Peter Christen Asbjørnsen, translated by H.L. Brækstad, Folk and Fairy Tales, page 285
2. A yarmulke-like hat worn as an element of ghetto fashion.
3. (anatomy) The calvaria, the top part of the skull, covering the cranial cavity containing the brain.
4. (botany) Any of several species of flowering plants of the genus Scutellaria, in the Lamiaceae family.
5. (historical) A torture device for compressing the skull.