Rem is a unit for measuring the amount of ionizing radiation that would be required to produce biological damage, or the stage of sleep characterized by rapid eye movement.(noun)
See rem in Webster's New World College Dictionary
noun pl. rem
Origin: r(oentgen) e(quivalent), m(an)
noun pl. REMs
Origin: r(apid) e(ye) m(ovement)
See rem in American Heritage Dictionary 4
Origin: r(oentgen) e(quivalent in) m(an).
Origin: r(apid) e(ye) m(ovement).
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