详细解释:【计】 随机存取装置, 快速存取数据, 快速存取设备
【化】 拉德
【医】 拉德(测量电离放射吸收量单位)
英语解释：
名词 rad:
a unit of absorbed ionizing radiation equal to 100 ergs per gram of irradiated materialthe 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)同义词：radian