noun ダウンロード 🔗共有 八面体 A polyhedron with eight faces; the regular octahedron has regular triangles as faces and is one of the Platonic solids. Examples : "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。 math figure AIとチャット語彙ゲーム読解練習