Definition of tennis court oath in English English dictionary
(June 20, 1789) Oath taken by deputies of the Third Estate in the French Revolution. Believing that their newly formed National Assembly was to be disbanded, the deputies met at a nearby tennis court when they were locked out of their usual meeting hall at Versailles. They vowed never to separate until a written constitution was established for France. Their solidarity forced Louis XVI to order the clergy and the nobility to join with the Third Estate in the National Assembly