verb (v)

• engage in plotting or enter into a conspiracy, swear together(verb.cognition)

  Example:
  They conspired to overthrow the government.
  

  Synonym:
  cabal, complot, conjure, machinate
  

  source: wordnet30
• act in unison or agreement and in secret towards a deceitful or illegal purpose(verb.cognition)

  Example:
  The two companies conspired to cause the value of the stock to fall.
  

  Synonym:
  collude
  

  source: wordnet30
• To make an agreement, esp. a secret agreement, to do some act, as to commit treason or a crime, or to do some unlawful deed; to plot together.(verb)

  source: webster1913
• To plot; to plan; to combine for.(verb)

  source: webster1913