1. 1. A form of backing storage giving direct access and a storage capacity in excess of 2000,000 words for each drum. The drum is a cylinder with a magnetizable surface with several recording tracks. The drum is continuously rotated (up to 7000 rpm) while a group of read/write heads enter and access data with transfer rates as high as ten million bits per second. In computing, it is an early form of magnetic storage device.
2. 磁鼓；【修】鼓式[形][D，DR]
语源
Middle English: from Middle Dutch or Low German tromme, of imitative originearly 18th cent.: from Scottish Gaelic and Irish druim 'ridge'
