detestable (adj.)youdaoicibaDictYouDict[detestable 词源字典]
early 15c., from Middle French détestable (14c.), from Latin detestabilis "execrable, abominable," from detestari (see detest). Related: Detestably.[detestable etymology, detestable origin, 英语词源]
incontestable (adj.)youdaoicibaDictYouDict
1670s, from French incontestable, from in- "not" (see in- (1)) + contestable (see contest (v.)). Related: Incontestably.