From the Dutch phrase "Voort seg ik!" literally meaning "Forward say I!". It was then adapted by South Africans into voetsek, and then eventually "footsack" in English.

It was originally meant for dogs, but is now fairly commonly used against people as well, although in this context it's meant as a light-hearted "fuck off!"

The most common variation is the abbreviated "tsack", or the colloquial "tsek".
Dopie: Can I have a bite of your hotdog?
Salie: Footsack!

(or, more realistically)

Dopie: Gimme a stuk of your boerewors roll!
Salie: 'tsek!
by BiltongBoy July 7, 2006
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