noun
1. : a line in a doubly refracting medium that is parallel to the direction in which all components of plane-polarized light travel with the same speed
2. : optical axis 1
noun
1. : a line in a doubly refracting medium that is parallel to the direction in which all components of plane-polarized light travel with the same speed
2. : optical axis 1
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012