noun🔗Share八面体A polyhedron with eight faces; the regular octahedron has regular triangles as faces and is one of the Platonic solids."In math class, we learned that an octahedron is a shape with eight faces. "数学の授業で、八面体は8つの面を持つ図形だと学びました。mathfigureChat with AIVocabulary GamePractice Reading