The verb punish came into English from the old French puniss-, extended prp. stem of punir (to punish) from the Latine punire, from poenire from poena, which is related to the Greek ποινή (poene; punishment, penalty).
From the same root: punishment, punishable, punitive, punitory
In modern Greek:
ποινή: punishment, sentence, penalty
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ποινή (poene) - poena → poenire → punire → punir → puniss- → punish
See the blog: English words of no apparent Greek origin at: http://ewonago.blogspot.com/
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