Origin: Greek suffix -ism
Ostracism has 3 different meanings across 1 category:
the state of being banished or ostracized (excluded from society by general consent)
"the association should get rid of its elderly members--not by euthanasia, of course, but by Coventry"
the act of excluding someone from society by general consent
In ancient Athens (and some other cities), the temporary banishment by popular vote of a citizen considered dangerous to the state.