- incredible (adj.)
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- early 15c., "unbelievable, surpassing belief as to what is possible," from Latin incredibilis "not to be believed, extraordinary," from in- "not" (see in- (1)) + credibilis "worthy of belief" (see credible). Used c. 1400 in a now-extinct sense of "unbelieving, incredulous." Related: Incredibly; incredibility.