E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Jouvence (2 syl.).
You have been to the fountain of Jouvencei.e. You have grown young again. This is a French phrase. Jouvence is a town of France in the department of Saône-et-Loire, and has a fountain called la fontaine de
Jouvence; but Jouvence means also youth, and la fontaine de jouvence may be rendered the fountain of youth. The play on the word gave rise to the tradition that whoever drank of this fountain would become young again.