1 [C] a wooden or metal bar fixed to a wall, which you can hang things on （固定在墙上用来挂物件的）横杆，横档: a towel/curtain/picture rail 挂毛巾╱窗帘╱图画的横杆 ☞picture on page C7 见C7页插图

2 [C] a bar which you can hold to stop you from falling (on stairs, from a building, etc) （楼梯等的）栏杆，扶手

3 [C] [usu.pl] each of the two metal bars that form the track that trains run on 铁轨；轨道

4 [U] the railway system; trains as a means of transport 铁路系统；火车: rail travel/services/fares 乘火车旅行；列车服务；火车票价