Sylae

(σῦλαι). The Greek equivalent of the modern “letters of marque and reprisal.” When a Greek State had been insulted or injured by citizens of some other State, yet was unable or unwilling formally to declare war, it often gave a sort of license or commission to individuals to make reprisals upon the property and citizens of the offending nation. This was called σύλας or σῦλα διδόναι.