The Collaborative International Dictionary of English v.0.48:

Alcade \Al*cade"\ ([a^]k*k[=a]d"), n.
   Same as Alcaid.
   [1913 Webster]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

ALCADE, Span. law. The name of a judicial officer in Spain, and in those
countries which have received the body of their laws from those of Spain.