adj. 25B6; adjective his favourite aunt : BEST-LOVED, most-liked, favoured, dearest; preferred, chosen, choice.
25B6; noun
Brutus was Caesar's favourite : (FIRST) CHOICE, pick, preference, pet, darling, the apple of one's eye; informal golden boy; Brit. informal blue-eyed boy/girl; N. Amer. informal fair-haired boy/girl.
the favourite fell at the first fence : EXPECTED WINNER, front runner.