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

abrasion \abra"sion\, n. l. abrasio, fr. abradere. see
   abrade.
   1. the act of abrading, wearing, or rubbing off; the wearing
      away by friction; as, the abrasion of coins.
      1913 webster

   2. the substance rubbed off. --berkeley.
      1913 webster

   3. med.
      a a superficial excoriation of skin or mucous membranes.
          --as
      b erosion of the tooth substance --as
          1913 webster
see also:
abrade 

[2] : WordNet (r) 2.0

abrasion
     n 1: an abraded area where the skin is torn or worn off syn: scratch,
           scrape, excoriation
     2: erosion by friction syn: attrition, corrasion, detrition
     3: the wearing down of rock particles by friction due to water
        or wind or ice syn: grinding, attrition, detrition
see also:
scratch scrape excoriation attrition corrasion detrition 
grinding 

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

102 moby thesaurus words for "abrasion":
   ablation, abrasive, abstraction, atomization, attrition, beating,
   blemish, break, brecciation, buffing, burn, burnishing, chafe,
   chafing, check, chip, comminution, concussion, crack, crackle,
   craze, crumbling, crushing, cut, deduction, detrition,
   disintegration, dressing, erasure, erosion, filing, flash burn,
   fracture, fragmentation, fray, frazzle, fretting, gall, galling,
   gash, granulation, granulization, grating, grazing, grinding, hurt,
   incision, injury, laceration, lesion, levigation, limation,
   mashing, mortal wound, mutilation, polishing, pounding, powdering,
   puncture, purification, rasping, refinement, removal, rent, rip,
   rubbing away, run, rupture, sandblasting, sanding, scald, scorch,
   scouring, scrape, scraping, scratch, scratching, scrub, scrubbing,
   scuff, second-degree burn, shining, shredding, slash, smashing,
   smoothing, sore, stab, stab wound, subduction, sublation,
   subtraction, taking away, tear, third-degree burn, trauma,
   trituration, wear, wearing away, wound, wounds immedicable,
   wrench

Abrasion >> A Words
Abrasion, definition of term: Abrasion
abrasion_pag1.html