Believer

来自Big Physics

wiktionary

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From Middle English bilevar, bileever, belever, equivalent to believe +‎ -er.


etymonline

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believer (n.)

1540s, "one who has faith in religion," agent noun from believe. From c. 1600 as "one who gives credence (to anything) without personal knowledge, one firmly persuaded of the truth of something."