1(coll.) bicycle; bike (esp. in Hong Kong, Taiwan and southern China and, more generally, used across China to refer to a bike-share bicycle)
Examples
yú chǔn愚蠢qí骑zhe着méi yǒu没有zhá闸de的dān chē单车。
愚蠢骑着没有闸的单车。
Stupidity is riding a bike that doesn't have brakes.
刚想骑单车去，却下起雨了。
I was thinking that I would go there by bicycle, but it began to rain.