Then you become the real taxidriver who understands just one sign of the whole sign language – it’s the one that yells I WANNA TAXI! TAXI! STOP! […] A taxidriver like that learns to get to know one gesture only but every form of it: The uppity-mellow lifting of the left arm of little Madison Avenue ladies whose right hand is holding a leash with a choking lap-sized dog; […]
Source: wiktionary