| principal axis | แกนมุขสำคัญ [คณิตศาสตร์๑๙ ก.ค. ๒๕๔๗] |
| principal axis | (n) a line that passes through the center of curvature of a lens so that light is neither reflected nor refracted, Syn. optic axis |
| Hauptachsentheorem { n } [ math. ] | principal axis theorem [Add to Longdo] |