to be work one's self into a frenzy of anger, stress, or otherwise unpleasent moods towards another person
stop getting all busy on me man!
Bowel or urinal relief by a dog in a permitted location
I took my big dog out so he could do his business by lifting his leg on that tree
Muffy goes out every morning to do her business in front of the neighbor's house
Non-descriptive excuse someone gives you when they're trying to get out of meeting or spending time with you. Similar to "I have plans". Basically means they're not that into you.
Girl: Hey, you're on vacation this week right? Wanna come over and hang out?
Guy: Sorry I can't; I'm busy
Biz-ness. Meaning cool or legit.
Joe: I just aced my biology final.
Steve: Business.