heptahedronPronunciation: /ˌhɛptəˈhiːdrən, -ˈhɛd-/Definition of heptahedron noun (plural heptahedra /-drə/ or heptahedrons) a solid figure with seven plane faces. Derivatives heptahedral adjective Origin: late 17th century: from hepta- 'seven' + -hedron, on the pattern of words such as polyhedronheptahedron in other Oxford dictionaries Definition of heptahedron in the US English dictionary
