Why is the ninth month called September?
1803, from French contre-danse, altered from English country dance by folk etymology from French contra "against," suggested by the arrangement of the partners in the dance. The dances and the name were taken up in France c. 1720s and from there passed to Spain and Italy (Spanish, Italian contra danza) then back to English.
genre of dance for several couples. The contredanse was an 18th-century French development of the English country dance (q.v.) and was performed into the 19th century by French, English, and German aristocrats and bourgeoisie. Contredanses at first used only the country dance's "longways" formations, in which each couple danced its way to the head of a double line (men on one side, women on the other). At the head of the line, the pair danced a duet before relinquishing the position to the next couple in line. Later contredanses on the Continent appropriated square formations from country dancing; these became the popular cotillion and quadrille (qq.v.). Cooperation was required to execute the various geometric figures of the contredanses because steps were often not standardized; e.g., the longways duet could be performed differently by successive couples.