Cabbie's income (5)
I believe the answer is:
'cabbie's income' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for fares that I've seen before include "Gets on" , "Taxi passengers" , "Charges for bus or train rides" , "Moneys paid to ride on train or bus" , "Charges for public vehicles" .)