toughened

from WordNet (r) 3.0 (2006)

toughened
    adj 1: physically toughened; "the tough bottoms of his feet"
           [syn: {tough}, {toughened}] [ant: {tender},
           {untoughened}]
    2: made hard or flexible or resilient especially by heat
       treatment; "a sword of tempered steel"; "tempered glass"
       [syn: {tempered}, {treated}, {hardened}, {toughened}] [ant:
       {unhardened}, {untempered}]

from The Collaborative International Dictionary of English v.0.48

Toughen \Tough"en\, v. i. & t. [imp. & p. p. {Toughened}; p. pr.
   & vb. n. {Toughening}.]
   To grow or make tough, or tougher.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

29 Moby Thesaurus words for "toughened":
      annealed, backed, calcified, callous, calloused, case-hardened,
      crusted, crusty, crystallized, fossilized, granulated, hardened,
      hornified, incrusted, indurate, indurated, lapidified, ossified,
      petrified, reinforced, rigidified, sclerotic, set, solidified,
      steeled, stiffened, strengthened, tempered, vitrified

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