Zuchetto n. : A skullcap covering the tonsure, worn under the berretta. The pope's is white; a cardinal's red; a bishop's purple; a priest's black.

Example:


Taxonomy
zucchetto, popes, the Roman, free encyclopedia, Cardinal, Roman Catholic Church, mitre, zuchetto, Philippi, scarlet, zucchetti, churches, search, pileolus, Latin, clerics, heads, damp.

Defination from the web:
... the altar, usually made of brass or wood and known as a funghellino is used in some churches to hold the zuchetto during that part of the service. ... mitre is being worn; it is placed inside it (a mitre is bottomless, so the zuchetto sits on the head while the mitre is around it) ...