It defines the feeling of not being able to intake anything without regurgitating it up again but of a slight shade of green. But Duckbread is safe and with a little fluid of the non alcohol variety will stay and settle ones insides, sometimes.
A Duckbread Hangover is like a 7 Star Hangover! You want to crawl up into a ball and hibernate!
Friend 2: "Ahh mate, its Duckbread, nothing stays down"
Friend 1: "Nooo waay, i'm not surprised after those 8 jager bombs in a row!"