(hos′pi·təl·ər) noun
1. One cared for or supported in a hospital.
2. The title of the chief resident official in certain London hospitals which were originally religious foundations. See HOSTELER (def. 2). Also hos′pi·tal·ler.

(hos′pi·təl·ər) noun
A member of one of various charitable brotherhoods or military orders of the Middle Ages, of which the best known is the Knights Hospitalers of St. John of Jerusalem, which originated during the crusades in a hospital built at Jerusalem by merchants of Amalfi and dedicated to St. John the Baptist. When the order had to move its seat elsewhere, it was known as Knights of Malta and Knights of Rhodes.