A Tudor bonnet (also referred to as a doctor's cap or round cap) is a traditional, softly crowned, wide-brimmed cap, with a tassel hanging from a cord that runs around the cap. As the name suggests, the Tudor bonnet was widely worn in England and elsewhere during the Tudor period (1485–1603).
Nowadays, the cap is strongly associated with academic tradition. It is typically worn as part of academic dress by someone who has earned a research or professional doctorate or a full higher doctorate.
It can also be worn by someone who has received an honorary doctorate. At certain educational institutions, the cap distinguishes university officials, such as the esquire bedell, the university marshal, the president of the student association, and members of the university council.
The cap is worn as traditional headgear with gowns and serves as a symbol of appropriate headgear, particularly for officials of guilds and civic offices. Tudor bonnets can be made from velvet or fabric, usually black, but sometimes in other colours. The cord and tassel can come in various colours. Gold is common on academic caps, but at Oxford and some other institutions, a black ribbon tradition is standard.
In many North American educational institutions, doctorate holders typically wear instead a soft, rimless tam or a traditional square academic hat (mortarboard). The biretta also sometimes appears among holders of theological degrees or officials of religious institutions.
