Percent

google

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mid 16th century: from per + cent, perhaps an abbreviation of pseudo-Latin per centum .

wiktionary

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From New Latin per centum(“by the hundred”).

etymonline

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percent

"by the hundred;" with a preceding numeral expressing a proportion of the whole amount, 1560s, per cent, from Modern Latin per centum "by the hundred" (see per and see hundred). Until early 20c. often treated as an abbreviation and punctuated accordingly.