means A team sport played on horseback in which riders use long-handled mallets to drive a small ball into the opposing goal — and, by extension, the name borrowed for variants like water polo and even a shirt collar.

from The word travels a long road east to west. English took it in the 19th century from Balti, a Tibetan-related language of the western Himalayas, where 'polo' meant simply 'ball.' British players encountered the game in India — itself an heir to far older mounted ball-games played across Central Asia and Persia for centuries — and carried both the sport and its short, sturdy name back home, from which it spread worldwide.