Definition of "Neutralize" :

verb: make chemically neutral

"She neutralized the solution."

verb: make ineffective by counterbalancing the effect of

"Her optimism neutralizes his gloom."

verb: make incapable of military action

verb: get rid of (someone who may be a threat) by killing

"The double agent was neutralized."

verb: make politically neutral and thus inoffensive

"The treaty neutralized the small republic."

verb: oppose and mitigate the effects of by contrary actions