What is -er?
1.
The addition of the suffix -ER to an adjective, to create a noun. Thereby turning a characteristic or behaviour into a descriptive name. If someone behaves in a gay way, they become a 'gayer' or if they're being greedy they are a 'fatter'.
Stop picking on me man. You're such a mean-ER.
OR
You'll never get laid if you keep being such a stupider
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