mackjock
A mackjock is a cocky, smug, and obnoxious person who thinks they're the best at everything. They'll talk your ear off just to prove it.
'You're just a nobody. I'm the somebody.'
'I got 10 likes on my post. You got zero. You're literally invisible.'
'I can do a pull-up and still make a TikTok. You can't even do a push-up.'