phrygian cap

from The Collaborative International Dictionary of English v.0.48

Phrygian cap \Phryg"i*an cap`\
   A close-fitting cap represented in Greek art as worn by
   Orientals, assumed to have been conical in shape. It has been
   adopted in modern art as the so-called {liberty cap}, or {cap
   of liberty}.
   [Webster 1913 Suppl.]