Academic dress

Academic dress is a traditional form of clothing for academic settings, mainly tertiary (and sometimes secondary) education, worn mainly by those who have been admitted to a university degree (or similar), or hold a status that entitles them to assume them (e.g., undergraduate students at certain old universities). It is also known as academical dress,academicals, and, in the United States, as academic regalia.

Contemporarily, it is commonly seen only at graduation ceremonies, but formerly academic dress was, and to a lesser degree in many ancient universities still is, worn daily. Today the ensembles are distinctive in some way to each institution, and generally consists of a gown (also known as a robe) with a separate hood, and usually a cap (generally either a square academic cap, a tam, or a bonnet). Academic dress is also worn by members of certain learned societies and institutions as official dress.

The academic dress found in most universities in the Commonwealth of Nations and the United States is derived from that of the universities of Oxford and Cambridge, which was a development of academic and clerical dress common throughout the medieval universities of Europe.

...
Wikipedia