1 [U] the waste gas that comes out of a vehicle, an engine or a machine （车辆、发动机、机器等排出的）废气: car exhaust fumes/emissions 汽车废气

2 [C] (also exhaust pipe (US 美) tailpipe) a pipe (particularly at the back of a car) through which waste gas escapes from an engine or machine 排气管（尤指汽车后面的） ☞picture at car 见car插图