Also a
slang term for an
alcoholic drink - frequently of the
refreshing variety.
More specifically, a hangover cure, as referenced in John Barleycorn below. I'd suggest either a screwdriver or a bloody mary as good choices, but YMMV. The theory goes that the body doesn't like to be suddenly deprived - anecdotal evidence suggests a small amount of alcohol would be beneficial. The antioxidants & fructose in orange juice won't do any harm, either.
From John Barleycorn
http://sunsite.berkeley.edu/London/Writings/JohnBarleycorn/chapter34.html
...I was suffering from the morning sickness of the steady, heavy drinker. What I needed was a pick-me-up, a bracer.
from The Road to Success in Informal English
http://www.geocities.com/informalenglish/B.html
bracer(n) :an alcoholic drink taken as a stimulant.