Gypsy Cab

The Historical Dictionary of American Slang, A-G has citations for "gypsy," meaning an independent migratory trucker, from 1953 and 1960.

A "gypsy cab" is an unlicensed taxi. The use became popular in the 1960s.


23 November 1964, New York Times, pg. 39:
Gypsy Cabs Cruise City - and Thrive - Illegally
(...)
The gypsy drivers are permitted by law to respond only to telephoned or otherwise pre-arranged appointments. But in practice they stop when hailed and thrive in competition with the regular, city-licensed cab drivers, who are bitterly resentful of the gypsies.