The Collaborative International Dictionary
Decahedra
Decahedron \Dec`a*he"dron\, n.; pl. E. Decahedrons, L. Decahedra. [Pref. deca- + Gr. 'e`dra a seat, a base, fr. 'e`zesthai to sit: cf. F. d['e]ca[`e]dre.] (Geom.) A solid figure or body inclosed by ten plane surfaces.
Wiktionary
decahedra
n. (plural of decahedron English)