noun (n)

• erosion by friction(noun.process)

  Synonym:
  abrasion, attrition, corrasion
  

  source: wordnet30
• the wearing down of rock particles by friction due to water or wind or ice(noun.phenomenon)

  Synonym:
  abrasion, attrition, grinding
  

  source: wordnet30
• effort expended in moving one object over another with pressure(noun.act)

  Synonym:
  friction, rubbing
  

  source: wordnet30
• A wearing off or away.(noun)

  source: webster1913