The Collaborative International Dictionary
Cerevis
Cerevis \Cer"e*vis\ (s[e^]r"[-e]*v[i^]s; G. ts[e^]r`[~e]*v[=e]s"), n. [G., fr. L. cerevisia, cervisia, beer.] A small visorless cap, worn by members of German student corps. It is made in the corps colors, and usually bears the insignia of the corps.
Wiktionary
cerevis
n. A small cap, with no peak, worn by members of German student corps