anorak

Concise Oxford English Dictionary © 2008 Oxford University Press:
anorak/ˈanərak/

▶noun

• 1 a waterproof jacket, typically with a hood.

• 2 Brit. informal a studious or obsessive person with largely solitary interests.

– derivatives
anoraky adjective,
anorakish adjective.

– origin 1920s: from Greenland Eskimo anoraq.