backup .名詞 n.
1、幫助援助支援 military backup 軍事援助
2、替代物備用品支援人員， 後備， 後補， 助手 a backup singer for Stevie Wonder 史蒂維·旺德的伴唱歌手 The hospital has a backup generator in case there is a power failure. 醫院有備用發電機以防停電。 She once sang backup for Madonna. 她曾經爲麥當娜伴唱。
3、(流水受阻造成的)阻塞氾濫(車輛等)擁塞
4、備份檔案 a backup disk 備份磁盤 Have you kept a backup of this file? 你把這檔案備份了嗎? We had no computer backup and had to rely on old paper files to reconstruct the records. 我們沒有計算機備份，只得靠落後的紙檔案重做記錄。
