Definition of


  1. (noun, state) a recurring sleep state during which dreaming occurs; a state of rapidly shifting eye movements during sleep
  2. (noun, quantity) (Roentgen Equivalent Man) the dosage of ionizing radiation that will cause the same amount of injury to human tissue as 1 roentgen of X-rays

via WordNet, Princeton University

Alternate forms of Rem

Hypernyms: radioactivity unit, sleep, slumber

Origin of the word Rem

  1. "unit for measuring radiation," 1947, acronym of roentgen equivalent man. more

via Online Etymology Dictionary, ©2001 Douglas Harper

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