Emily Dickinson Lexicon

CAS'TEL-LAN, n. [Sp. castellan; Fr. chatelain. See Castle.]

A governor or constable of a castle. In Poland, the name of a dignity or charge; a kind of lieutenant of a province, commanding part of a palatinate under a palatine. The castellans are senators, of the lower class, sitting, in the diets, on low seats behind the palatines. – Encyc.