/
ˈɒstrəsʌɪz/
v.
  - exclude from a society or group.
 - (in ancient Greece) banish (a citizen) from a city for five or ten years by popular vote.
 
Derivative
Etymology
C17: from Gk ostrakizein, from ostrakon ‘shell or potsherd’ (on which names were written in voting to banish unpopular citizens).