Akademik

a taxicab that cruises for customers although it is licensed only to respond to calls

: a taxicab licensed only to answer calls ; especially : such a cab that cruises in search of passengers illegally

a taxicab that is licensed only to pick up passengers on call by telephone, but that often illegally seeks passengers on the street.

[1960-65, Amer.]

gypsy cab,

U.S. a taxicab that may be hired by a passenger at its place of business but is not licensed to cruise the streets seeking passengers.

Synonym Study livery cab.