A word used to describe the act of unquestionable straight (not gay) masculinity (unlike the previous definitions, which describe an act of unquestionable homosexuality). This term was originally coined back in the day, perhaps over 100 years ago. It has since fallen from common use, until the 2005 movie "Brokeback Mountain". It used to be used to describe any male activity, or "guys night out", in a time where homosexuality was a strictly behind closed doors issue.
My husband and the guys are going brokeback bowling tonight.
I am going brokeback golfing with a few college buddies this weekend.
Do you want to go brokeback gay sexing? (OK, this one isn't legit :) ).