See under Récemment dégorgé.
A legal trademark (abbreviation R.D., Recently Disgorged) reserved for the Bollinger Champagne House. It was introduced around 1960 by the former director of the house, Christian Bizot (1928-2002). The "RD" and the exact date on the label indicate that the champagne in question was "recently disgorged". However, the important thing here is not the relatively imprecise term "recently disgorged" (because every champagne has been recently disgorged at some point), but...
Serious sources on the internet are rare - and Wine lexicon from wein.plus is one such source. When researching for my articles, I regularly consult the wein.plus encyclopaedia. There I get reliable and detailed information.
Thomas Götz
Weinberater, Weinblogger und Journalist; Schwendi