decastyle

from The Collaborative International Dictionary of English v.0.48

Decastyle \Dec"a*style\, a. [Gr. ?; de`ka ten + sty`los a
   column.] (Arch.)
   Having ten columns in front; -- said of a portico, temple,
   etc. -- n. A portico having ten pillars or columns in front.
   [1913 Webster]