perron

from The Collaborative International Dictionary of English v.0.48

Perron \Per"ron\, n. [F.] (Arch.)
   An out-of-door flight of steps, as in a garden, leading to a
   terrace or to an upper story; -- usually applied to
   medi[ae]vel or later structures of some architectural
   pretensions.
   [Webster 1913 Suppl.]