Manifesto

google

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mid 17th century: from Italian, from manifestare, from Latin, ‘make public’, from manifestus ‘obvious’ (see manifest1).

wiktionary

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Since the mid 17th century, from Italian manifesto, from manifestare, from Latin manifestō(“to make public”). Doublet of manifest.

etymonline

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manifesto (n.)

"public declaration explaining reasons or motives for a course of actions done or planned," 1640s, from Italian manifesto "public declaration explaining past actions and announcing the motive for forthcoming ones," originally "proof," from Latin manifestus "plainly apprehensible, clear, apparent, evident" (see manifest (adj.)), also used as a noun, "obvious facts, palpable things."