Jabbleknacker
A person who talks trash and acts like they're the best person in the world when they're not.
My brother is a jabbleknacker. He said I was a f***ing f*** and told me I'd never be cool.
My friend is a jabbleknacker. She said my math test was a f***ing disaster and called me a f***ing dweeb.
My teacher is a jabbleknacker. She said I was a disgrace and told me I was a total f***ing loser.
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