ostracize

In ancient Greece, prominent citizens whose power or influence threatened the stability of the state could be exiled by a practice called ostracism. Voters would elect to banish another citizen by writing that citizen's name down on a potsherd. Those receiving enough votes would then be subject to temporary exile from the state (usually for ten years). The English verb ostracize can mean "to exile by the ancient method of ostracism," but these days it usually refers to the general exclusion of one person from a group at the agreement of its members. Ostracism and ostracize derive from the Greek ostrakizein ("to banish by voting with potsherds"). Its ancestor, the Greek ostrakon ("shell" or "potsherd"), also helped to give English the word oyster.