friction

[1]	abrasion , clash , rubbing , abrading , chafing , fretting , attrition , scraping , grating , erosion
[2]	disagreement , rubbing , discord , conflict , contention , dispute , dissension , disharmony , controversy , dissent , bickering , argument , wrangling , ill feeling , ill will , bad blood , animosity , rivalry , hostility , antagonism , strife
[3]	detrition , rubbing