(also safety belt) noun [C] a strap that is fixed to the seat in a car or plane and that you wear around your body so that you are not thrown forward if there is an accident （汽车或飞机座位上的）安全带: to fasten/unfasten your seat belt 系上╱解开安全带 ☞Look at belt. 参看belt。 ☞picture at car 见car插图