Definition of

R

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

via WordNet, Princeton University

Origin of the word R

  1. In a circle, meaning "registered (trademark)," first incorporated in U.S. statues 1946. Three Rs (1825) said to have been given as a toast by Sir W. Curtis (1752-1829). R&R "rest and relaxation," first recorded 1953, Amer.Eng.; R&B "rhythm and blues" (type of popular music) first attested 1949, Amer.Eng. more

via Online Etymology Dictionary, ©2001 Douglas Harper

Words that sound like R

r-2, ra, rahu, raiu, rare, rariora, raw, ray, re, rear, rehear, rewa-rewa, rewire, rh, rhea, rho, ri, rio, rira, ro, roar, roarer, roe, roi, roue, row, rower, ru, ru 486, rue

via soundex() Hash Matches

Note: If you're looking to improve your vocabulary right now, we highly recommend Ultimate Vocabulary Software.

Word of the Moment

Cubitus

hinge joint between the forearm and upper arm and the corresponding joint in the forelimb of a quadruped