incredible (adj.)youdaoicibaDictYouDict[incredible 词源字典]
early 15c., "unbelievable," from Latin incredibilis "not to be believed," 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.[incredible etymology, incredible origin, 英语词源]