A more Continental variation of Drynuary, the practice of giving your liver a break after the ravages of the holidays. Literally, "Happy Winter Liver".
Like Ciao and Aloha, can be used as a salutation or goodbye.
Etymology: combination and play on the French word for Winter (hiver) and the booze-targeting organ (liver).
After mainlining Gloria Ferrer and Armagnac for all of December, it's time to say Bon L'(h)iver!
Bon L'(h)iver! I'll have a club soda with lime, please.