Definition of "Intervention" :

noun: care provided to improve a situation (especially medical procedures or applications that are intended to relieve illness or injury)

noun: (law) a proceeding that permits a person to enter into a lawsuit already in progress; admission of person not an original party to the suit so that person can protect some right or interest that is allegedly affected by the proceedings

"The purpose of intervention is to prevent unnecessary duplication of lawsuits."

noun: the act or fact of interposing one thing between or among others

noun: the act of intervening (as to mediate a dispute, etc.)

"It occurs without human intervention."

noun: a policy of intervening in the affairs of other countries