Headrest
an automotive safety feature
A headrest is something which supports the head. It is usually a suitably shaped part of the back of a chair or of a front seat in a car.
![](http://up.wiki.x.io/wikipedia/commons/thumb/8/85/417096_12_full.jpg/220px-417096_12_full.jpg)
It is designed to support passenger's shoulder part and neck to prevent whiplash in cases of crash at the rear.