Bucks Fizz is an
alcoholic drink made with orange juice and champagne and
grenadine.
The drink is named after
London's
Bucks Club where it was invented, and first served, by one of it's barmen, Mr McGarry, in
1921.
Buck's Fizz is the English version of the French
Mimosa, & predates the Mimosa by 3 years.
Note: Although the version listed here, with grenadine, may be the original usage, most British people will understand 'Buck's Fizz' to refer to a mixture of orange juice and champagne; i.e. it is the usual British term for what Americans would call a 'Mimosa'.
Sometimes, where real Champagne is not available or cannot be afforded, a sparkling white wine or
perry is used in its place.