Where does the word pè come from in pè kalòt? why do we say pè?

I don't know where it comes from.  But I had seen it and ...heard it. A man had smashed a poor woman's face between BOTH of his hands with such brutal force that it's a wonder she still had all her teeth.  Maybe they call it that because some people use both of their hands.
Yon pè kalòt, yon kalòt, yon pè sabò, yon sabò, yon palavire, yon souflèt, yon pè souflèt, or yon pataswèl, they're all a slap in the face.

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