(in Britain) the formal name for O level
noun 1. life insurance with premiums paid throughout the lifetime of the insured.
noun 1. Mathematics. a point in a domain in which a given function of a complex variable is analytic.
- Ordinary rating
noun 1. a rank in the Royal Navy comparable to that of a private in the army
noun 1. Optics, Crystallography. the part of a doubly refracted ray whose velocity within a crystal is the same in any direction. noun 1. the plane-polarized ray of light that obeys the laws of refraction in a doubly-refracting crystal Compare double refraction, extraordinary ray