Answer: hailer

AnswerCrossword Clue
HAILERWould-be taxi fare
HAILERCab caller
HAILERCab rider-to-be
HAILERArm raiser on the street, often
HAILERGreeter from a distance.
HAILEROne summoning a taxi
HAILERProspective taxi fare
HAILERGreeter
HAILERWhom a hack watches out for
HAILERCab catcher
hailercall or greeting
hailerto call out or signal to
hailerone who greets (to address courteously on meeting)
hailerto greet