octahedral, octo-, a.
(ɒktəˈhiːdrəl, -ˈhɛdrəl)
Also octaedral, octoedral.
[f. late L. octa(h)edros, a. Gr. ὀκτάεδρ-ος eight-sided: see octahedron and -al1.]
Having the form of an octahedron; contained by eight plane (esp. triangular) faces.
| 1758 Reid tr. Macquer's Chym. I. 222 The crystals of Alum are octaedral... These octaedral solids are triangular pyramids, having their angles cut away, so that four of their surfaces are hexagons, and the other four triangles. 1796 Hatchett in Phil. Trans. LXXXVI. 292 Various modifications between the octoedral figure and the cube. 1811 Pinkerton Petral. l. 312 Some detached crystals of octahedral iron. 1869 Phillips Vesuv. iii. 94 Crystallized in cubes and octahedral forms. |
b. Of or belonging to an octahedron.
| 1878 Gurney Crystallogr. 88 At each angle of the octahedral face. |