look up anything, like your first name:
1. Allihater
An inconspicuous hater who hates on peaceful, beach-dwelling, non-haters.
Groucho is an allihater for hating on us non-haters in silence.
2. Allihater
The act of using ur arms like an alligator mouth, with your two middle fingers as the teeth. Used on excessive haters who wont shut up.

NOTE: THE MIDDLE FINGERS SHOULD NEVER TOUCH.
*Billy wont stop hating out loud*

*Allihater motion at Billy*
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