特殊用法coordinate trihedral1.坐标三面形left-handed trihedral1.左手三面形moving trihedral1.活动三面形polar trihedral1.极三面形principal trihedral1.主要三面形reciprocal trihedral1.倒三面体(的), 倒三面形(的)right-handed trihedral1.右手三面形