Zucchetto is a small, skullcap-like hat worn by members of the Catholic clergy. It is also known as a pileolus or a skullcap. Other synonyms for zucchetto include berrettino, which is a diminutive version of the berretta, and Saturno, which is a wider-brimmed version of the skullcap. In some areas, it is also called a solideo, which is a Latin word meaning "alone" and is used to denote the solitary nature of the hat. The zucchetto can come in various colors to denote the rank of the wearer, such as red for cardinals, purple for bishops, and white for the pope.