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rad

Definitions of rad
  1. noun
    a unit of absorbed ionizing radiation equal to 100 ergs per gram of irradiated material
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    type of:
    radioactivity unit
    a measure of radioactivity
  2. noun
    the unit of plane angle adopted under the Systeme International d'Unites; equal to the angle at the center of a circle subtended by an arc equal in length to the radius (approximately 57.295 degrees)
    synonyms: radian
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    type of:
    angular unit
    a unit of measurement for angles
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