Words related to credo

experto crede 
Latin, "take it from one who knows" ("Aeneid," xi.283); dative singular of expertus (see expert (adj.)) + imperative singular of credere "to believe" (see credo).
grant (v.)
in early use also graunt, early 13c., "to allow, permit (something); consent to (a prayer, request, etc.)," from Old French graanter, variant of creanter "assure, promise, guarantee, swear; confirm, authorize, approve (of)," from Latin credentem (nominative credens), present participle of credere "to believe, to trust" (see credo). From c. 1300 as "transfer possession of in any formal way." Meaning "admit to be true, acknowledge" in English is from c. 1300; hence to take (something) for granted "regard as not requiring proof" (1610s). The irregular change of -c- to -g- in Old French is perhaps from influence of garantir. Related: Granted; granting.
incroyable (n.)

1796, a name for the French fop or dandy of the period of the Directory (1795-1799),  from French incroyable, literally "incredible" (15c.), from in- "not, opposite of, without" (see in- (1)) + croire "to believe," from Latin credere "to believe" (see credo). Said to be so called from their extravagant dress, and also, according to OED, from a favorite expression among them ("C'est vraiment incroyable").

miscreant (adj.)

c. 1300, "non-Christian, misbelieving, pagan, infidel;" early 15c., "heretical, unbelieving," from Old French mescreant "disbelieving" (Modern French mécréant), from mes- "wrongly" (see mis- (2)) + creant, present participle of creire "believe," from Latin credere "to believe" (see credo). Meaning "villainous, vile, detestable" is from 1590s. Related: Miscreance; miscreancy.

recreant (adj.)

c. 1300, recreaunt, "confessing oneself to be overcome or vanquished, admitting defeat, surrendering, ready to yield in a fight," also a word of surrender, from Old French recreant "defeated, vanquished, yielding, giving; weak, exhausted; cowardly" (also used as a noun), present-participle adjective from recroire "to yield in a trial by combat, surrender allegiance," literally "believe again;" perhaps on notion of "take back one's pledge, yield one's cause," from re- "again, back" (see re-) + croire "entrust, believe," from Latin credere (see credo).

Non sufficit ... nisi dicat illud verbum odiosum, quod recreantus sit. [Bracton, "De Legibus et Consuetudinibus Angliæ," c. 1260]

The extended meaning "cowardly" in English is from late 14c. The meaning "unfaithful to duty" is from 1640s. Middle English also had a verb recreien "to be cowardly, yield in battle" (mid-14c.).

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