1. very tired, beaten down, exhausted
2. in need of an update
I had a hard day at work, I am so beat city.
Why are you wearing stirrup pants? Those are so beat city.
Completely worn out, dead, kicked, lame, etc, needing to be replaced.
Stems from the term "beat", used to describe a bowl of marijuana that can't be hit again.
I'm 24, I still live with my parents, and they grounded me for leaving the garage door open yesterday. It's beat city.