Someone who is totally the shit. One badass motherfucker, as some might say. Someone who is your Bro, of great friend, but too great to simply call Bro. A term to be used when you want to think outside of the Bro Box.
The extent, capacity, or degree of one's boss-like nature or boss-ness in a given situation or as an accumulation of all of their life undertakings as a whole.
Said by an individual performing a stunt or difficult physical/social maneuver: "Yo, witness this bossiosity!"
Said to an associate while witnessing something impressive: "Yo, gander this bossiosity!"
Said in a whisper-like voice when in awe of something ridiculous unfolding before your very eyes: "Ahhh, bossiosity!"