An adjective to describe someone who displays extremehomosexual behaviour to the extent that the word 'batty' is not sufficient enough to describe them.
Dan is so batacious, he cannot stop slapping my batty whenever I bend down!
When you're so down bad that you need an extension of the phrase to define just exactly how down bad you are. This version of down bad doesn't always have to be applied sexually. It could mean you're down bad for a delightful date, or you're just doing shitty in life overall.
In other words, you're either doomed or desperate as hell.
Chad: "Bro, my girlfriend broke up with me AND I failed finals."
Brad: "Man. You down badarious, dude."