To be equipped with a condom. Usually as a precaution for the possibility of a sexual encounter, even when no such situation is immediately or obviously forthcoming.
Bob: Man, I totally hooked up with Betty at that party last night. Luckily I was condarmed, or she would never have let me do anything.
Jack: Dude, I bumped into Jill in the street the other night. We would totally have hit it off, but I didn't have any protection...
John: Unlucky mate... You should've been condarmed when you went out, so if stuff happens it's never a problem.