serial number
noun [ C ] uk/ˈsɪə.ri.əl ˌnʌm.bər/ us/ˈsɪr.i.əl ˌnʌm.bɚ/
序列号，编号
one of a set of numbers that is put on things produced in large quantities, such as computers, televisions, paper money, etc. so that each has a different number and can be recognized