R (European Roma Rights Centre) v Immigration Officer at Prague Airport
WordNet
noun
(1) The length of a line segment between the center and circumference of a circle or sphere
(2) The 18th letter of the Roman alphabet
(3) (physics) the universal constant in the gas equation: pressure times volume = R times temperature; equal to 8.3143 joules per kelvin per mole
(4) A unit of radiation exposure; the dose of ionizing radiation that will produce 1 electrostatic unit of electricity in 1 cc of dry air