Noun
One who, or that which, is foremost, original, etc.
The editio princeps, or first edition of a book.
Source: en.wiktionary.orgThe princeps copy, clad in blue and gold. John Ferriar
According to the abbey's records, in which he was called princeps Australium Saxonum, Eadwinus nomine (Eadwine leader of the South Saxons), he bequeathed estates to them in his will, although the document itself has not survived. Source: Internet
Competing magnates, those called in charters "dux" or "princeps" (that is, leaders), may have brought the kings to power. Source: Internet
He also tasked his grandsons as summer rulers of the city when most of the government were on holiday in the country or attending religious rituals, and, for that task, granted them the title of princeps. Source: Internet
Charles, titling himself maior domus and princeps et dux Francorum, did not appoint a new king and nobody acclaimed one. Source: Internet
Diocletian completed the work of fully restoring the empire, but declined the role of princeps and became the first emperor to be addressed regularly as domine, "master" or "lord". Source: Internet