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R

Definition:

1. [noun] a unit of radiation exposure; the dose of ionizing radiation that will produce 1 electrostatic unit of electricity in 1 cc of dry air
   Synonyms: oentgen
   
   
2. [noun] (physics) the universal constant in the gas equation: pressure times volume = R times temperature; equal to 8.3143 joules per kelvin per mole
   Synonyms: gas constant, univesal gas constant
   
   
3. [noun] the 18th letter of the Roman alphabet
   
   
4. [noun] the length of a line segment between the center and circumference of a circle or sphere
   Synonyms: adius
   
   

Synonyms:

• Search for synonyms for R

Related Words:

• semidiameter
• radius of curvature

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