(photography) A lens which produces an image similar in detail and angular perspective to the view produced by the human eye, as distinct from a wide-angle lens or a telephoto lens.

(economics) a good for which demand increases when income increases and falls when income decreases but price remains constant, i.e. with a positive income elasticity of demand.

plural of normal space

(topology) A regular space with the additional property that for every disjoint pair of closed sets in that space, there is a disjoint pair of open sets which contain the closed sets, respectively.

plural of normal subgroup

(medicine, slang, UK, derogatory) Peculiar or odd. / (medicine, slang, UK, derogatory) Of a patient, having lesser intellect.

A lifestyle similar to that before the advent of COVID-19, but where some precautions such as social distancing, hand sanitising, contact tracing protocols, etc., will be in place to help prevent future outbreaks.

Normal profit refers to the revenue required for a firm to stay within a market in the long-run.

(idiomatic) The current prevailing situation, when it has emerged recently, differs dramatically from the previous one and is expected to remain.

plural of surface normal