alcaide UK /ælˈkeɪd/US /ælˈkaɪdi/ noun2 •(historical) The governor or commander of a Spanish or Portuguese fortress or prison.Soon after Mr. Petticrew arrived at Gibraltar, he came to Tetuan in his majesty's ship Seahorse, to acquaint the alcaide that he had orders from the king of Great Britain,[…]. — 1768 •A caid. formsalcaides