hackney
n. countablen. a horse that is kept for riding or driving, or a carriage that you can hire. In modern times, it mostly refers to the famous black taxis found in London.
n. a horse used for ordinary riding or driving, or a carriage kept for hire. In contemporary British English, the term survives primarily in the legal designation 'hackney carriage' for a licensed taxicab.
The city still issues licenses for every hackney carriage on the road.
While the term sounds old-fashioned, a hackney carriage is simply the official name for a London black cab.
The transition from horse-drawn hackney coaches to motorized taxicabs marked a significant shift in urban transport, though the traditional licensing terminology remains largely unchanged in municipal law.
The senses "a horse" and "(a means of transport) available for hire" derive from the fact that many horses were kept for hire in the London borough of Hackney. The place name is from Old English *Hacan īeġ "Hacan's Isle" (or "Hook's Island"), referring to dry land in a marsh.
Often used as a modifier in the compound 'hackney carriage'.