polo (n.)

ball game of eastern origin resembling field hockey played on horseback, 1872, Anglo-Indian polo, from Balti (Tibetan language of the Indus valley) polo "ball," related to Tibetan pulu "ball." An ancient game in south Asia, first played in England at Aldershot, 1871. Water polo is from 1876 (in early versions players sometimes paddled about on barrels or in canoes). Polo shirt (1892) originally was a kind worn by polo players.

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Definitions of polo from WordNet
polo (n.)
a game similar to field hockey but played on horseback using long-handled mallets and a wooden ball;
Polo (n.)
Venetian traveler who explored Asia in the 13th century and served Kublai Khan (1254-1324);
Synonyms: Marco Polo