The act of being saucy, aka drunk or high, partying, bromances,etc. There are different sauce levels, depending how much fun you're having. Most people who are involved in saucetivities use the word bro 24/7. If you want to participate in a saucetivity, you must use the word bro in every sentence possible, even if it doesnt make sense.
Hey taylor, wanna raise our sauce levels tonight, I can't wait for the saucetivities bro.
Bro, what saucetivity is raging tonight? I dont know Blake, but its gonna be a rager bro.