allegeyoudaoicibaDictYouDict[allege 词源字典]
allege: [14] Allege is related to law, legal, legislation, legation, and litigation. Its original source was Vulgar Latin *exlitigāre, which meant ‘clear of charges in a lawsuit’ (from ex- ‘out of’ and litigāre ‘litigate’). This developed successively into Old French esligier and Anglo- Norman alegier, from where it was borrowed into English; there, its original meaning was ‘make a declaration before a legal tribunal’.

Early traces of the notion of making an assertion without proof can be detected within 50 years of the word’s introduction into English, but it took a couple of centuries to develop fully. The hard g of allegation suggests that though it is ultimately related to allege, it comes from a slightly different source: Latin allēgātiō, from allēgāre ‘adduce’, a compound verb formed from ad- ‘to’ and lēgāre ‘charge’ (source of English legate and legation).

=> law, legal, legation, legislation, litigation[allege etymology, allege origin, 英语词源]
empiricalyoudaoicibaDictYouDict
empirical: [16] Despite their formal resemblance, empirical and empire are completely unrelated. Empirical comes ultimately from the Greek adjective émpeiros ‘skilled or experienced in’, a compound formed from the prefix en- ‘in’ and peira ‘attempt, trial’ (a relative of English expert, peril, pirate, and repertory). From this were derived successively the noun empeiría ‘experience’ and empeirikós, which English acquired via Latin empiricus.
=> expert, peril, pirate, repertory
successive (adj.)youdaoicibaDictYouDict
early 15c., from Medieval Latin successivus "successive," from success-, stem of Latin succedere "to come after" (see succeed). Related: Successively.