favorite (n.)

"person or thing regarded with especial liking," 1580s, from Middle French favorit, perhaps via Italian favorito, noun use of past participle of favorire, from favore, from Latin favorem "inclination, partiality, support" (see favor (n.)).

Especially, "a person who gains dominant influence over a superior" (1590s). In racing, attested from 1813. As an adjective, by 1711. Favorite son in figurative use is from 1788. As a corresponding noun, "person who promotes the interests of another," Latin had fautor, hence Old French fauteur, Middle English fautour (early 14c.), but it has perished along with its fem. form fautress.