unforgiving

from WordNet (r) 3.0 (2006)

unforgiving
    adj 1: unwilling or unable to forgive or show mercy; "a surly
           unforgiving old woman" [ant: {forgiving}]
    2: not to be placated or appeased or moved by entreaty; "grim
       determination"; "grim necessity"; "Russia's final hour, it
       seemed, approached with inexorable certainty"; "relentless
       persecution"; "the stern demands of parenthood" [syn: {grim},
       {inexorable}, {relentless}, {stern}, {unappeasable},
       {unforgiving}, {unrelenting}]

from The Collaborative International Dictionary of English v.0.48

Unforgiving \Unforgiving\
   See {forgiving}.

from Moby Thesaurus II by Grady Ward, 1.0

25 Moby Thesaurus words for "unforgiving":
      bowelless, cruel, dog-eat-dog, flinty, hard, harsh, heartless,
      inclement, inexorable, merciless, pitiless, relentless,
      remorseless, ruthless, uncompassionate, uncompassioned, unfeeling,
      unmerciful, unpitiful, unpitying, unremorseful, unsympathetic,
      unsympathizing, unyielding, without mercy

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