manifest

1350–1400; (adj.) Middle English < Latin manifestus, manufestus detected in the act, evident, visible; (v.) Middle English manifesten < Middle French manifester < Latin manifestāre, derivative of manifestus. See manus, infest

3. See display.

English manifest exists as three parts of speech: in historical order, adjective (late 14th century), verb (early 15th), and noun (mid-16th). Manifest ultimately comes from Latin manifestus (also manufestus ) and its derivatives, meaning “caught red-handed, caught in the act, evident, plain to see, readily understood.” The first element, mani- (or manu- ), obviously derives from manus “hand”; the element - festus, however, is very rare and occurs in only one other Latin adjective, infestus “hostile, antagonistic, troubled.”
The Latin sense of manifestus “evident, plain to see” is the earliest sense in English. The Latin verb manifestāre “to make visible, indicate, make plain, disclose,” a derivative of manifestus, is, along with the Middle French verb manifester, the source of the English verb.
The noun sense of manifest, “a list of a ship’s cargo or goods,” appeared in the late 17th century and comes from Italian manifesto “a public declaration, especially a written declaration,” which dates from the early 17th century. That Italian word is, of course, the source of English manifesto, “a public declaration of intentions, opinions, etc.,” which happens to be one of the less common meanings of English manifest.