[1] : The Collaborative International Dictionary of English v.0.48

merciful \mer"ciful\, a. mercy + -ful.
   1. full of mercy; having or exercising mercy; disposed to
      pity and spare offenders; unwilling to punish. opposite of
      merciless.
      1913 webster

            the lord, the lord god, merciful and gracious. --ex.
                                                  xxxiv. 6.
      1913 webster

            be merciful, great duke, to men of mold. --shak.
      1913 webster

   2. unwilling to give pain; compassionate.
      1913 webster

            a merciful man will be merciful to his beast. --old
                                                  proverb.
      1913 webster

   syn: compassionate; tender; humane; gracious; kind; mild;
        clement; benignant.
        1913 webster -- mer"cifully, adv. --
        mer"cifulness, n.
        1913 webster
see also:
merciless mer"cifully mer"cifulness 

[2] : WordNet (r) 2.0

merciful
     adj 1: showing or giving mercy; "sought merciful treatment for the
            captives"; "a merciful god" ant: merciless
     2: characterized by mercy, and compassion; "compassionate
        toward disadvantaged people"; "kind to animals"; "a humane
        judge" syn: kind
     3: used conventionally of royalty and high nobility; "our
        merciful king"
see also:
merciless kind 

[3] : Moby Thesaurus II by Grady Ward, 1.0

92 moby thesaurus words for "merciful":
   accepting, all-knowing, all-powerful, all-seeing, all-wise,
   almighty, beneficent, benign, benignant, big, bleeding, boundless,
   changeless, charitable, clement, commiserative, compassionate,
   condolent, considerate, creating, creative, easy, easygoing,
   eternal, eternally the same, everlasting, forbearant, forbearing,
   forgiving, generous, gentle, glorious, good, gracious, hallowed,
   highest, holy, human, humane, immortal, immutable, indulgent,
   infinite, just, kind, kindly, lax, lenient, liberal, limitless,
   loving, luminous, magnanimous, majestic, making, melting, mild,
   moderate, numinous, omnipotent, omnipresent, omniscient, one,
   patient, permanent, perpetual, pitiful, pitying, radiant, ruth,
   ruthful, sacred, shaping, soft, softhearted, sovereign, sparing,
   supreme, sympathetic, sympathizing, tender, tenderhearted,
   thoughtful, timeless, tolerant, ubiquitous, unbounded, unchanging,
   undefined, understanding, unlimited, warmhearted

Merciful >> M Words
Merciful, definition of term: Merciful
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