defile

Noun

• a narrow pass (especially one between mountains)

Verb

• spot, stain, or pollute
  • The townspeople defiled the river by emptying raw sewage into it
    

• make dirty or spotty, as by exposure to air; also used metaphorically
  • The silver was tarnished by the long exposure to the air
    
  • Her reputation was sullied after the affair with a married man
    

• place under suspicion or cast doubt upon
  • sully someone's reputation
    

Related words

• Synonyms: 
  gorge , foul , befoul , maculate , tarnish , stain , sully , corrupt , taint , cloud