1.something really cool.2.used to express joy in something/someone.3.to express that something is really or very good.
1. Yo man this rollercoaster in the shiznit!
2. Dang i can't believe you stood up to that bully! you're the shiznit!
3. This pizza is the shiznit.
see also the shit.
a word invented by a girl named Kryctee from NJ in the early 90's. now widely known everywhere and used to death, it has never been rightly credited.
that girl Kryctee was the shiznit. she was the most unique person i ever met. she made everyone around her snort soda out their noses from laughing so hard.