Definition of R (symbol)

R (symbol): This much-used symbol has many meanings in medicine. They include:

  1. Respiration: a nurse's note of "R20" is shorthand for 20 respirations (breaths) per minute.
  2. Right: A doctor's note of a burn on the "R digit 5" places the burn on the right little finger or toe.
  3. Roentgen, an international unit of X-radiation or gamma-radiation.
  4. In chemistry, a radical.
  5. On a prescription, R (or Rx), recipe, which is Latin for "to take".


Last Editorial Review: 6/14/2012

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