According to the Thrash Unreal Songfacts, the title doesn't appear in the lyrics. "Thrash Unreal" is something their producer Butch Vig came up with.
If she wants to dance and drink all night well theres no one that can stop her.
Shes going until the house lights come up or her stomach spills onto the floor.
This night is gonna to end when were damn well ready for it to be over.
Worked all week long now the music is playing on our time.