Taxi (3)
'taxi' is the definition.
(I know that taxi can be written as cab)
This is all the clue.
(Other definitions for cab that I've seen before include "Transport" , "A taxi in New York" , "Driver's compartment, in lorry say" , "Organisation to collect money made from crime" , "It has the authority to confiscate the proceeds of crime, in short" .)
'taxi' is the definition.
(I know that minicab is a type of taxi)
This is all the clue.
(Other definitions for minicab that I've seen before include "Type of taxi" , "Metered vehicle for hire" , "It can't be hailed in the street" , "Car used as taxi" , "Type of car hire" .)