Source : Webster's Revised Unabridged Dictionary (1913)

Prismoid \Pris"moid\ (pr[i^]z"moid), n. [Cf. F. prismto["i]de.]
   A body that approaches to the form of a prism.

Source : WordNet®

prismoid
     n : a prismatoid whose bases are polygons having the same number
         of sides and whose other faces are trapezoids or
         parallelograms