A Brendan Bevola is a very broad and alternative name for a drink or beverage that is usually alcoholic
Derived from the Australian Football player, 'Brendan Fevola', the "Fev" in Fevola is much similar to the abbreviation of "Beverage" which is 'Bev'. Often you'll hear this at parties in Australia, more commonly in Victoria. Very basically, the term is just an alternative to the word "drink" or "beverage" or any specific drink.
Guy 1: "ay lads we good to leave for Mick's in an hour?"
Guy 2: "fuck, hang on bro, i gotta go pick up some Brendan Bevolas from the Bottle-o first!"
Guy 1: "oh true cunt i gotta grab some meself!"