(slang) Carrying and consuming two alcoholic beverages simultaneously
2009, Tucker Max, I Hope They Serve Beer in Hell, page 112I saunter around flirting with waitresses and bartenders and strippers, double-fisting vodka
2010, Fieldy, Got the Life: My Journey of Addiction, Faith, Recovery, and Korn, linkI only felt like myself when I was drunk Double-fisting beer was pretty typical for me back in the day.