The cotillion (also cotillon or French country dance) is a social dance, popular in 18th-century Europe and America.

The English word "cotillion" is a variation of the French "cotillon" (which does not have "i" in the last syllable). The French word originally meant "petticoat (underskirt)". There are two etymological theories as to how "underskirt" became a dance's name:

-The dance "revealed the underskirt";

-It is from the lyrics of a song that accompanied the dance: "My friend, when I dance, does my petticoat show? (or: does my petticoat move well?’).

The cotillion was introduced into England by 1766 and to America in about 1772. In England from that time onwards there are a large number of references stressing its universal popularity in the best and highest circles of society, and many teaching manuals were published to help recall the vast number of changes that were invented.

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