Emily Dickinson Lexicon

PET'AL-ISM, n. [Gr. πεταλισμος. See Petal.]

A form of sentence among the ancient Syracusans, by which they proscribed a citizen whose wealth or popularity alarmed their jealousy, or who was suspected of aspiring to sovereign power; temporary proscription, or banishment for five years. The mode was to give their votes by writing his name on a leaf. Petalism in Syracuse answered to ostracism in Athens. – Encyc. Cyc.