E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Quanquam or Cancan.
A slang manner of dancing quadrilles permitted in the public gardens of Paris, etc. The word cancan is a corruption of the Latin quamquam, a term applied to the exercises delivered by young theological students before the divinity professors. Hence it came to signify babble, jargon, anything crude, jejune, etc.