E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Hoary, grey-headed. This word is much used in Paris to signify good, delicate, exquisite in flavour, delicious, de bon goût. It was originally applied to wine which is improved by age. Thus we hear commonly in Paris the expression, Voilà du vin qui est bien chenu (mellow with age). Sometimes gris (grey with age) is substituted, as, Nous en boirons tant de ce bon vin gris (Le Tresor des Chansons Nouvelles, p. 78). The word, however, is by no means limited to wine, but is applied to well-nigh everything worthy of commendation. We even hear Chenu Reluit, good morning; and Chenu sorgue, good night. Reluit, of course, means sunshine, and sorgue is an old French word for evening or brown. Chenument = à merveille.