The Collaborative International Dictionary of English v.0.48:

Largess \Lar"gess\, Largesse \Lar"gesse\ (l[aum]r*j[e^]s" or
   l[aum]r"j[e^]s), n. [F. largesse, fr. large. See Large, a.]
   1. Liberality; generosity; bounty. [Obs.]
      [1913 Webster]

            Fulfilled of largesse and of all grace. --Chaucer.
      [1913 Webster]

   2. A present; a gift; a bounty bestowed.
      [1913 Webster]

            The heralds finished their proclamation with their
            usual cry of "Largesse, largesse, gallant knights!"
            and gold and silver pieces were showered on them
            from the galleries.                   --Sir W.
                                                  Scott.
      [1913 Webster]

WordNet (r) 3.0 (2006):

largess
    n 1: a gift or money given (as for service or out of
         benevolence); usually given ostentatiously [syn: largess,
         largesse]
    2: liberality in bestowing gifts; extremely liberal and generous
       of spirit [syn: munificence, largess, largesse,
       magnanimity, openhandedness]

Moby Thesaurus II by Grady Ward, 1.0:

57 Moby Thesaurus words for "largess":
   Trinkgeld, benevolence, bigheartedness, bonus, boon, bounteousness,
   bountifulness, bounty, bribe, compliment, consideration, donative,
   double time, easy purse strings, favor, fee, free hand, freedom,
   freehandedness, freeheartedness, freeness, generosity,
   generousness, gift, givingness, graciousness, gratuity, gravy,
   grease, great heart, greatheartedness, honorarium, hospitality,
   lagniappe, largeheartedness, largeness, liberality, liberalness,
   magnanimity, munificence, open hand, open heart, openhandedness,
   openheartedness, palm oil, perks, perquisite, pourboire, premium,
   present, salve, something extra, sportula, sweetener, tip,
   unselfishness, welcome