verb (v)

• seize and take control without authority and possibly with force; take as one's right or possession(verb.possession)

  Example:
  He usurped my rights.
  

  Synonym:
  arrogate, assume, seize, take over
  

  source: wordnet30
• take the place of(verb.social)

  Example:
  Gloom had usurped mirth at the party after the news of the terrorist act broke.
  

  source: wordnet30
• To seize, and hold in possession, by force, or without right; as, to usurp a throne; to usurp the prerogatives of the crown; to usurp power; to usurp the right of a patron is to oust or dispossess him.(verb)

  source: webster1913
• To commit forcible seizure of place, power, functions, or the like, without right; to commit unjust encroachments; to be, or act as, a usurper.(verb)

  source: webster1913