Definition of "Containment" :

noun: the act of containing; keeping something from spreading

"The containment of the AIDS epidemic."

noun: (physics) a system designed to prevent the accidental release of radioactive material from a reactor

noun: a policy of creating strategic alliances in order to check the expansion of a hostile power or ideology or to force it to negotiate peacefully

"Containment of communist expansion was a central principle of United States' foreign policy from 1947 to the 1975."