WordNet: rhombohedron

a parallelepiped bounded by six similar faces (either rhombuses or parallelograms)

• hypernym parallelepiped, parallelepipedon, parallelopiped, parallelopipedon

• hypernym hexahedron

rhombohedron

• (englanti) rhombohedral (derivationally related)
• (suomi) romboedri (synonyymi)