The Collaborative International Dictionary of English v.0.48:

Moorish \Moor"ish\, a. [See 1st Moor, and cf. Morris,
   Moresque.]
   Of or pertaining to Morocco or the Moors; in the style of the
   Moors.
   [1913 Webster]

   Moorish architecture, the style developed by the Moors in
      the later Middle Ages, esp. in Spain, in which the arch
      had the form of a horseshoe, and the ornamentation
      admitted no representation of animal life. It has many
      points of resemblance to the Arabian and Persian styles,
      but should be distinguished from them. See Illust. under
      Moresque.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Moorish architecture
    n 1: a style of architecture common in Spain from the 13th to
         16th centuries; characterized by horseshoe-shaped arches
         [syn: Moorish, Moorish architecture]