conspire

verb

1. engage in plotting or enter into a conspiracy, swear together

   verb.cognition

   Examples

   They conspired to overthrow the government.

   Synonyms cabal complot conjure machinate

   Source: WordNet 3.0

2. act in unison or agreement and in secret towards a deceitful or illegal purpose

   verb.cognition

   Examples

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

   Synonyms collude

   Source: WordNet 3.0

3. 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

4. To plot; to plan; to combine for.

   verb

   Source: webster1913