Buck-rider (A).

A dummy fare who enables a cabman to pass police-constables who prevent empty cabs loitering at places where cabs will be likely to be required, as at theatres, music-halls, and large hotels. A cabman who wants to get at such a place under hope of picking up a fare gives a “buck” a shilling to get into his cab that he may seem to have a fare, and so pass the police.