scour1
  
  v.
   - clean or brighten by vigorous rubbing, typically with an abrasive or detergent. 
▸remove (dirt or unwanted matter) by rubbing in such a way.
 - (of running water) erode (a channel or pool).
 - (of livestock) suffer from diarrhoea.
 
n.
  - the action of scouring or the state of being scoured.
 - 
(also scours)
 diarrhoea in livestock, especially cattle and pigs.
 
 
  Derivative
  
  Etymology
  ME: from MDu., Mid. Low Ger. schūren, from OFr. escurer, from late L. excurare ‘clean (off)’.
 
  
    
scour2
  
  v.
  - subject to a thorough search.
 - move rapidly.
 
 
  Etymology
  ME: rel. to obs. scour ‘moving hastily’, of unknown origin.