1 [C] a large pipe or wire that carries water, gas or electricity between buildings （自来水或煤气的）总管，主要管道；（电力的）总线，干线: The water main has burst. 总水管爆裂了。

2 the mains [pl] (Brit 英) the place where the supply of gas, water or electricity to a building starts; the system of providing these services to a building （楼房内煤气、水或电源的）总开关；（煤气、水或电力在建筑物里的）网络: Turn the water off at the mains. 关掉水管的总开关。mains gas/water/electricity 管道煤气；自来水；交流电源