The Collaborative International Dictionary of English v.0.48:

Oriel \O"ri*el\, n. [OF. oriol gallery, corridor, LL. oriolum
   portico, hall, prob. fr. L. aureolus gilded, applied to an
   apartment decorated with gilding. See Oriole.] [Formerly
   written also oriol, oryal, oryall.]
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   1. A gallery for minstrels. [Obs.] --W. Hamper.
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   2. A small apartment next a hall, where certain persons were
      accustomed to dine; a sort of recess. [Obs.] --Cowell.
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   3. (Arch.) A bay window. See Bay window.
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            The beams that thro' the oriel shine
            Make prisms in every carven glass.    --Tennyson.
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   Note: There is no generally admitted difference between a bay
         window and an oriel. In the United States the latter
         name is often applied to bay windows which are small,
         and either polygonal or round; also, to such as are
         corbeled out from the wall instead of resting on the
         ground.
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The Collaborative International Dictionary of English v.0.48:

Oriol \O"ri*ol\, n.
   See Oriel.
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