(optics) the law that, for a ray incident on the interface of two media, the sine of the angle of incidence times the index of the refraction of the first medium is equal to the sine of the angle of refraction times the index of refraction of the second medium

comparative form of snell: more snell

A surname.

A Snellen chart.

superlative form of snell: most snell

A vision test using a Snellen chart.

plural of Snellen chart

A chart bearing letters or other symbols, used to test visual acuity.

plural of Snellen test

(UK dialectal, Northern England, Scotland) quickly; sharply; acutely; coldly / (UK dialectal, Northern England, Scotland, in speech) sharply; severely; tartly; curtly