authority Look up authority at Dictionary.com
early 13c., autorite "book or quotation that settles an argument," from O.Fr. auctorité (12c.; Mod.Fr. autorité), from L. auctoritatem (nom. auctoritas) "invention, advice, opinion, influence, command," from auctor "master, leader, author" (see author). Usually spelled with a -c- in English till 16c., when it was dropped, in imitation of the French. Meaning "power to enforce obedience" is from late 14c.; meaning "people in authority" is from 1610s. Authorities "those in charge, those with police powers" is recorded from mid-19c.