heptahedron

from The Collaborative International Dictionary of English v.0.48

Heptahedron \Hep`ta*he"dron\, n. [Hepta- + Gr. ? seat, base, fr.
   ? to sit: cf. F. hepta[`e]dre.] (Geom.)
   A solid figure with seven sides.
   [1913 Webster]