A drink of liquor taken when one has a hangover; a drink of liquor taken when one is recovering from drinking too much liquor. (Often the same type of liquor as one got drunk on.) deyim - "Oh, I'm miserable. I need some of the hair of the dog that bit me. That's some hangover you've got there, Bob. Here, drink this. It's some of the hair of the dog that bit you."