Origin of hackney
- Middle English hakenei probably after Hakenei , Hackney, a borough of London, England, where such horses were raised
From American Heritage Dictionary of the English Language, 5th Edition
- The senses "a horse" and "(a means of transport) available for hire" derive from the fact that many horses were kept in the London borough of Hackney, and were available for hire. The place name is from Old English Hacan ieg "Hacan's Isle" ("Hook's Island"), referring to dry land in a marsh.
- Probably from Hackney, formerly a town, now a borough of London, used for grazing horses before sale, or from Old French haquenee (“ambling mare for ladies”), Latinized in England to hakeneius (though some recent French sources report that the English usage predates the French)