The Collaborative International Dictionary of English v.0.48:

Maravedi \Mar`a*ve"di\, n. [Sp. maraved['i]; -- so called from
   the Mor[=a]bit[imac]n (lit., the steadfast), an Arabian
   dynasty which reigned in Africa and Spain. Cf. Marabout.]
   (Numis.)
   A small copper coin of Spain, equal to three mils American
   money, less than a farthing sterling. Also, an ancient
   Spanish gold coin.
   [1913 Webster]