backupn.后备
backup ared后备存储区
backup path后备路径
backup roll支承辊
backup yard后勤场地
backup file备份文件
backup line后备水带
backup tape备份带, 后备带
backup ring垫环
backup land预留地; 储备用地
backup lamp前照辅助灯,(英:reversing lamp)倒车灯