noun🔗Share候补，备用，后备。 A reserve or substitute."If the goalkeeper is injured, we have a backup."如果守门员受伤了，我们还有个候补队员。aidsystemtechnologytechnicalcomputingChat with AIVocabulary GamePractice Reading
noun🔗Share备份，副本 A copy of a file or record, stored separately from the original, that can be used to recover the original if it is destroyed or damaged."After the power failure, we had to restore the database from backup."停电后，我们不得不从备份中恢复数据库。computingtechnologybusinessChat with AIVocabulary GamePractice Reading
noun🔗Share堵塞，积聚。 An accumulation of material caused by a (partial) obstruction or (complete) blockage of the flow or movement of the material, or an accumulation of material that causes an overflow due to the flow being greater than the maximum possible flow."The accident caused a mile-long backup on the highway."事故导致高速公路上堵塞了长达一英里的车流。materialenvironmentdisastertechnicalindustryChat with AIVocabulary GamePractice Reading
noun🔗Share支援，后援。 (law enforcement) reinforcements"The police called in backup to handle the large crowd. "警察叫了支援来控制住大批人群。policelawmilitaryChat with AIVocabulary GamePractice Reading
adjective🔗Share备用的，后备的. Standby, reserve or extra."I am only a backup player."我只是个备用队员。technologycomputingbusinesselectronicstechnicalChat with AIVocabulary GamePractice Reading
adjective🔗Share备用的，后备的 That is intended as a backup."Make a backup copy of that file."为那个文件做一个备用拷贝。technologycomputingtechnicaldevicesystemutilityaidChat with AIVocabulary GamePractice Reading
adjective🔗Share备用的，后备的 Supporting, reinforcing; of or related to accompaniment"The teacher's clear explanations were a backup to the textbook's information. "老师清晰的讲解是对课本信息的补充和加强。aidfunctiontechnicalChat with AIVocabulary GamePractice Reading
