Word Study
rad
CIDE DICTIONARY
rad, n. [radiation absorbed dose.].
a unit of measurement of the amount of ionizing radiation absorbed by an object, equal to an energy of 100 ergs per gram of irradiated material (equal to 0.01 gray). [PJC]
OXFORD DICTIONARY
rad, n. (pl. same) radian.
rad, n. sl. a political radical.
rad, n. Physics a unit of absorbed dose of ionizing radiation, corresponding to the absorption of 0.01 joule per kilogram of absorbing material.
Etymology
radiation absorbed dose
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