The quantity of radiation that will have the same biological effect on man as the exposure to one roentgen of ordinary X ray.

【理】雷姆(测量吸收辐射程度之单位)。

Rapid eye movement; the periodic, repaid, jerky movement of the eyeballs under closed lids during stages of sleep associated with dreaming.

【心理】(作梦时)眼球急速活动。