chilia["e]dron

from The Collaborative International Dictionary of English v.0.48

Chiliahedron \Chil"i*a*hedron\, n. [Gr. chi`lioi a thousand + ?
   base, fr. ? to sit.]
   A figure bounded by a thousand plane surfaces [Spelt also
   {chilia["e]dron}.]
   [1913 Webster]