maverick

 
Pronunciation: /ˈmav(ə)rɪk/

noun

  • 1an unorthodox or independent-minded person: he’s the maverick of the senate
  • 2North American an unbranded calf or yearling.

adjective

  • unorthodox: a maverick detective

Origin:

mid 19th century: from the name of Samuel A. Maverick (1803–70), a Texas rancher who did not brand his cattle