Merriam-Webster Collegiate Dictionary - beguine

 I. noun  Usage: often capitalized  Etymology: Middle French  Date: 15th century a member of one of various ascetic and philanthropic communities of women not under vows founded chiefly in the Netherlands in the 13th century  II. noun  Etymology: American French beguine, from French beguin flirtation  Date: 1935 a vigorous popular dance of the islands of Saint Lucia and Martinique that somewhat resembles the rumba