R
01
半径, 半径
the length of a line segment between the center and circumference of a circle or sphere
02
罗马字母的第十八个字母, 字母R
the 18th letter of the Roman alphabet
03
伦琴, 辐射暴露单位
a unit of radiation exposure; the dose of ionizing radiation that will produce 1 electrostatic unit of electricity in 1 cc of dry air
04
普适气体常数, 气体常数R
(physics) the universal constant in the gas equation: pressure times volume = R times temperature; equal to 8.3143 joules per kelvin per mole
r
01
R级, 17岁以下需家长或监护人陪同观看
describing a motion picture that people under the age of 17 need a guardian or parent in order to watch it
Dialect
American
American
