verb (v)

• declare null and void; make ineffective(verb.social)

  Example:
  Strike down a law.
  

  Synonym:
  cancel
  

  source: wordnet30
• cause to die, especially suddenly(verb.contact)

  source: wordnet30
• cause to fall by or as if by delivering a blow(verb.contact)

  Example:
  Strike down a tree.
  

  Synonym:
  cut down, drop, fell
  

  source: wordnet30