The Collaborative International Dictionary of English v.0.48:

Valor \Val"or\, n. [OE. valour, OF. valor, valur, valour, F.
   valeur, LL. valor, fr. L. valere to be strong, or worth. See
   Valiant.] [Written also valour.]
   [1913 Webster]
   1. Value; worth. [Obs.] "The valor of a penny." --Sir T.
      More.
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   2. Strength of mind in regard to danger; that quality which
      enables a man to encounter danger with firmness; personal
      bravery; courage; prowess; intrepidity.
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            For contemplation he and valor formed. --Milton.
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            When valor preys on reason,
            It eats the sword it fights with.     --Shak.
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            Fear to do base, unworthy things is valor. --B.
                                                  Jonson.
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   3. A brave man; a man of valor. [R.] --Ld. Lytton.
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   Syn: Courage; heroism; bravery; gallantry; boldness;
        fearlessness. See Courage, and Heroism.
        [1913 Webster]

WordNet (r) 3.0 (2006):

valor
    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]

Moby Thesaurus II by Grady Ward, 1.0:

35 Moby Thesaurus words for "valor":
   Dutch courage, boldness, braveness, bravery, chivalrousness,
   chivalry, conspicuous gallantry, courage, courageousness,
   doughtiness, gallantness, gallantry, gallantry under fire,
   greatheartedness, heroicalness, heroism, intrepidity, intrepidness,
   knightliness, lionheartedness, manfulness, manhood, manliness,
   martial spirit, military spirit, pot-valor, prowess,
   soldierly quality, stalwartness, stoutheartedness, stoutness,
   valiance, valiancy, valorousness, virtue



The Devil's Dictionary (1881-1906):

VALOR, n.  A soldierly compound of vanity, duty and the gambler's
hope.
    "Why have you halted?" roared the commander of a division and
Chickamauga, who had ordered a charge; "move forward, sir, at once."
    "General," said the commander of the delinquent brigade, "I am
persuaded that any further display of valor by my troops will bring
them into collision with the enemy."