The Collaborative International Dictionary of English v.0.48:

Gallantry \Gal"lant*ry\, n.; pl. Gallantries. [F. galanterie.]
   1. Splendor of appearance; ostentatious finery. [Archaic]
      [1913 Webster]

            Guess the gallantry of our church by this . . . when
            the desk whereon the priest read was inlaid with
            plates of silver.                     --Fuller.
      [1913 Webster]

   2. Bravery; intrepidity; as, the troops behaved with great
      gallantry.
      [1913 Webster]

   3. Civility or polite attention to ladies; in a bad sense,
      attention or courtesy designed to win criminal favors from
      a female; freedom of principle or practice with respect to
      female virtue; intrigue.
      [1913 Webster]

   4. Gallant persons, collectively. [R.]
      [1913 Webster]

            Helenus, Antenor, and all the gallantry of Troy.
                                                  --Shak.

   Syn: See Courage, and Heroism.
        [1913 Webster]

WordNet (r) 3.0 (2006):

gallantry
    n 1: the qualities of a hero or heroine; exceptional or heroic
         courage when facing danger (especially in battle); "he
         showed great heroism in battle"; "he received a medal for
         valor" [syn: heroism, gallantry, valor, valour,
         valorousness, valiance, valiancy]
    2: courtesy towards women [syn: chivalry, gallantry,
       politesse]
    3: polite attentiveness to women

Moby Thesaurus II by Grady Ward, 1.0:

87 Moby Thesaurus words for "gallantry":
   Dutch courage, address, addresses, amenity, amorous pursuit,
   attention, backbone, boldness, braveness, bravery, chivalrousness,
   chivalry, conspicuous gallantry, courage, courageousness, court,
   courtesy, courting, courtliness, courtly politeness, dauntlessness,
   debauchery, debauchment, deference, dissipation, dissoluteness,
   doughtiness, duty, fastness, fortitude, gallantness,
   gallantry under fire, greatheartedness, guts, heroicalness,
   heroism, homage, honor, intrepidity, intrepidness, invincibility,
   knightliness, libertinage, libertinism, license, licentiousness,
   lionheartedness, manfulness, manhood, manliness, martial spirit,
   mettle, military spirit, noblesse oblige, poise, pot-valor,
   profligacy, prowess, rakishness, resolution, reverence, sand,
   savoir faire, serenade, soldierly quality, spirit, stalwartness,
   stoutheartedness, stoutness, suavity, suing, suit, tact, ten,
   unbridledness, unconquerableness, urbanity, valiance, valiancy,
   valor, valorousness, venery, virtue, wenching, whoring, wildness,
   wooing