Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun r

4 senses of r

Sense 1
roentgen, R -- (a unit of radiation exposure; the dose of ionizing radiation that will produce 1 electrostatic unit of electricity in 1 cc of dry air)
       => radioactivity unit -- (a measure of radioactivity)

Sense 2
gas constant, universal gas constant, R -- ((physics) the universal constant in the gas equation: pressure times volume = R times temperature; equal to 8.3143 joules per kelvin per mole)
       => constant -- (a number representing a quantity assumed to have a fixed value in a specified mathematical context; "the velocity of light is a constant")

Sense 3
R, r -- (the 18th letter of the Roman alphabet)
       => letter, letter of the alphabet, alphabetic character -- (the conventional characters of the alphabet used to represent speech; "his grandmother taught him his letters")

Sense 4
radius, r -- (the length of a line segment between the center and circumference of a circle or sphere)
       => length -- (the linear extent in space from one end to the other; the longest dimension of something that is fixed in place; "the length of the table was 5 feet")