oc·ta·he·dron
noun/ˌɒktəˈhiːdrən/
/ˌɑːktəˈhiːdrən/
(geometry)- a solid figure with eight flat sides, especially one whose sides are eight equal triangles
enlarge image八面体；正八面体 Word Originlate 16th cent.: from Greek oktaedron, neuter (used as a noun) of oktaedros ‘eight-faced’.