(名詞) 未注意行人或騎士就突然打開車門的汽車駕駛人。

If the cyclist had been merely knocked down but not killed, nobody would be calling for a bigger fine. Yet the action of the doorer would have been the same.

Ruining this particular doorer's life will do nothing to help the cyclist or improve safety for others.
—bubak, "Driver in fatal dooring will likely pay $110" (comment), Take the Lane, October 28, 2011

A new word has been coined in the Big Apple to cover an increasingly common cause of death or injury — doorers. That means someone opens the door of a stationary motor vehicle and sends a cyclist flying in to the path of a passing car or bus usually with dire consequences.
—Tom Sullivan, "Distracted drivers lead to injured pedestrians," The Record, October 5, 2012