n. an accumulation caused by clogging or a stoppagen. (computer science) a copy of a file or directory on a separate storage device
n. 倒车, 后退, 后援, 支持, 阻塞vt. 做备份a. 候补的, 支持的[计] 备份; DOS外部命令:通常使用于将硬磁盘上指定的文件复制到软盘上