WordNet (r) 3.0 (2006):

smart set
    n 1: the fashionable elite [syn: society, high society,
         beau monde, smart set, bon ton]

Moby Thesaurus II by Grady Ward, 1.0:

33 Moby Thesaurus words for "smart set":
   Vanity Fair, aristocracy, beau monde, beautiful people,
   best people, blue bloods, bon ton, cafe society, carriage trade,
   cream of society, drawing room, elite, fashionable society,
   good society, haut monde, high life, high society, in-crowd,
   jet set, jeunesse doree, monde, people of fashion, polite society,
   right people, salon, social register, societe, society,
   the Four Hundred, ton, upper crust, uppercut, world of fashion