Source : Webster's Revised Unabridged Dictionary (1913)

Magnanimous \Mag*nan"i*mous\, a.[L. magnanimus; magnus great +
   animus mind. See {Magnate}, and {Animus}.]
   1. Great of mind; elevated in soul or in sentiment; raised
      above what is low, mean, or ungenerous; of lofty and
      courageous spirit; as, a magnanimous character; a
      magnanimous conqueror.

            Be magnanimous in the enterprise.     --Shak.

            To give a kingdom hath been thought Greater and
            nobler done, and to law down Far more magnanimousan
            to assume.                            --Milton.

   2. Dictated by or exhibiting nobleness of soul; honorable;
      noble; not selfish.

            Both strived for death; magnanimous debate.
                                                  --Stirling.

            There is an indissoluble union between a magnanimous
            policy and the solid rewards of public prosperity
            and felicity.                         --Washington.

Source : WordNet®

magnanimous
     adj 1: noble and generous in spirit; "a greathearted general"; "a
            magnanimous conqueror" [syn: {greathearted}]
     2: generous and understanding and tolerant; "a heart big enough
        to hold no grudges"; "that's very big of you to be so
        forgiving"; "a large and generous spirit"; "a large
        heart"; "magnanimous toward his enemies" [syn: {big}, {large}]