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regatta Look up regatta at Dictionary.com
1652, name of a boat race among gondoliers held on the Grand Canal in Venice, from It. (Venetian dialect) regatta, lit. "contention for mastery," from regattare "to compete, haggle, sell at retail," possibly from recatare. The general meaning of "boat race, yacht race" is usually considered to have begun with a race on the Thames by that name June 23, 1775 (cf. OED), but there is evidence that it was used as early as 1768.
Henley Look up Henley at Dictionary.com
town on the Thames in Oxfordshire, site of annual regatta since 1839.