The act of being or acting like a ballbag. When a person acts stupidly or does something completely idiotic. Also when someone makes themselves look like an asshole or bell-end in public.
Friend One: "Oh look, Billy just told that girl he really fancies that she has a moustache."
Friend Two: "Yep, his ballbaggery knows no limits!"
Someone who likes to party get naked and drink rum... A LOT. She is beautiful and loud and vibrant. The worlds best and biggest ballbagger is a Kiwi lass by the name of Shelly.