wonk

Concise Oxford English Dictionary © 2008 Oxford University Press:
wonk/wɒŋk/

▶noun N. Amer. informal, derogatory

• 1 a studious or hard-working person.

  ■ (often policy wonk) a person who takes an excessive interest in minor details of political policy.

• 2 nautical slang an incompetent or inexperienced sailor, especially a naval cadet.

– derivatives
wonkish adjective.

– origin 1920s: of unknown origin.