subfusc
Concise Oxford English Dictionary © 2008 Oxford University Press:
subfusc /ˈsʌbfʌsk, sʌbˈfʌsk/
▶adjective literary dull or gloomy. ▶noun Brit. the formal clothing worn for examinations and formal occasions at some universities.
– origin C18: from L. subfuscus, from sub- ‘somewhat’ + fuscus ‘dark brown’.
'subfusc' also found in these Oxford entries:

