c. 1300, punishen, "inflict a penalty on," from Old French puniss-, extended present-participle stem of punir "to punish," from Latin punire "punish, correct, chastise; take vengeance for; inflict a penalty on, cause pain for some offense," earlier poenire, from poena "penalty, punishment" (see penal). Colloquial meaning "to inflict heavy damage or loss" is recorded from 1801, originally in pugilism. Related: Punished; punishing.
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<a href="https://www.etymonline.com/word/punisher">Etymology of punisher by etymonline</a>
Harper, D. (n.d.). Etymology of punisher. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/punisher