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

callus \cal"lus\ ka^l"lu^s, n. l. see callous.
   1. med.
      a same as callosity.
      b the material of repair in fractures of bone; a
          substance exuded at the site of fracture, which is at
          first soft or cartilaginous in consistence, but is
          ultimately converted into true bone and unites the
          fragments into a single piece.
          1913 webster

   2. hort. the new formation over the end of a cutting,
      before it puts out rootlets.
      1913 webster
see also:
callous callosity 

[2] : WordNet (r) 2.0

callus
     n 1: an area of skin that is thick or hard from continual
          pressure or friction as the sole of the foot syn: callosity
     2: bony tissue formed during the healing of a fractured bone
     3: botany an isolated thickening of tissue, especially a
        stiff protuberance on the lip of an orchid
     v 1: cause a callus to form on; "the long march had callused his
          feet"
     2: form a callus or calluses; "his foot callused"
     also: calli pl
see also:
callosity calli 

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

47 moby thesaurus words for "callus":
   philistinism, armor, benign tumor, callosity, callousness, cancer,
   carcinoma, corn, cyst, excrescence, flintiness,
   formidable defenses, fungosity, fungus, growth, hard heart,
   hard shell, hardenedness, hardheartedness, hardness,
   hardness of heart, heart of stone, imperviousness, induration,
   insensitiveness, insensitivity, intumescence, inuredness,
   malignant growth, metastatic tumor, mole, morbid growth, neoplasm,
   nevus, nonmalignant tumor, obduracy, obdurateness, outgrowth,
   proud flesh, rhinoceros hide, sarcoma, stoniness, thick skin,
   tumor, verruca, wart, wen

Callus >> C Words
Callus, definition of term: Callus
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