Prosperous

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late Middle English: from Old French prospereus, from Latin prosperus ‘doing well’.

wiktionary

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From Middle French prospereus, from Old French prosperer, from Latin prosperō(“I cause to succeed”), from Old Latin pro spere(“according to expectation”), from pro(“for”) + spes(“hope”).

etymonline

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prosperous (adj.)

early 15c., "favorable, auspicious, tending to bring success;" late 15c., "flourishing, successful, making good progress in anything good or desirable;" from Anglo-French prosperous, prospereus, Anglo-Latin prosperosus, or directly from Old French prospereus (15c.), from prosperer, extended form of prospere, from Latin prosperus "favorable, fortunate" (see prosper). Related: Prosperously; prosperousness.