serial port
noun [ C ] computing specialized uk/ˈsɪə.ri.əl ˌpɔːt/ us/ˈsɪr.i.əl ˌpɔːrt/
（电脑的）串行口，串行端口
a part of a computer where wires from other pieces of equipment can be connected to it, sending through information one bit (= unit of information) at a time
Compare: parallel port