The following is what the subfusc is all about … i found this interesting stuff in the oxford website…
Graduate Courses Handbook - Subfusc
Subfusc
The University Examination Decrees and Regulations state that all members of the University are required to wear academic dress with subfusc clothing when attending formal university events such as matriculation and university examinations. It consists of:
For women A dark skirt or trousers, a white blouse, black tie, black stockings and shoes,
and, if desired, a dark coat
For men A dark suit and socks, black shoes, a white bow tie and plain white shirt and collar
Candidates serving in HM Forces are permitted to wear uniform together with a gown. (The uniform cap is worn in the street and carried when indoors.)