In the Sengoku Period (Period of Warring States) (Japan), a vassal was referred to as jodai when he was assigned to take care of a castle directly controlled/managed by a daimyo (Japanese territorial lord) and administrative affairs and protect the castle from attacks.
戦国時代_(日本)に大名直轄の城の管理・政務・防衛にあたった家臣を指した。