The Collaborative International Dictionary of English v.0.48:

Milliner \Mil"li*ner\, n. [From Milaner an inhabitant of Milan,
   in Italy; hence, a man from Milan who imported women's
   finery.]
   [1913 Webster]
   1. Formerly, a man who imported and dealt in small articles
      of a miscellaneous kind, especially such as please the
      fancy of women. [Obs.]
      [1913 Webster]

            No milliner can so fit his customers with gloves.
                                                  --Shak.
      [1913 Webster]

   2. A person who designs, makes, trims, or deals in hats,
      bonnets, headdresses, etc., for women.
      [1913 Webster]

   Man milliner, a man who makes or deals in millinery, that
      occupation having been at one time predominantly performed
      by women; hence, contemptuously, a man who is busied with
      trifling occupations or embellishments.
      [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

milliner
    n 1: someone who makes and sells hats [syn: hatmaker,
         hatter, milliner, modiste]

Moby Thesaurus II by Grady Ward, 1.0:

53 Moby Thesaurus words for "milliner":
   antique store, apothecary, automobile showroom, bookstore, bootery,
   candy store, chemist, cigar store, clothiers, clothing store,
   confectionery, dress shop, drugstore, dry goods store, florists,
   fur salon, furniture store, gift shop, haberdashery,
   hardware store, hat shop, hatmaker, hatter, hobby shop,
   ironmongery, jewelers, jewelry store, leather goods store,
   liquor store, luggage shop, milliners, novelty shop, package store,
   pharmacy, saddlery, schlock house, schlock shop, secondhand shop,
   secondhand store, shoe store, smoke shop, specialty shop,
   sporting goods store, stationers, stationery store, sweater shop,
   sweet shop, thrift shop, tobacco store, tobacconists, toy shop,
   trimming store, used-car lot