disagree (to have or express a different opinion about something): I disagree strongly with you about this.
differ formal (to disagree): He and his wife differ in their interests.
oppose (to disagree strongly with someone or something): We oppose any changes to the policy.
take issue with (to disagree with): I must take issue with you on that subject.
not see eye to eye (not agree with): My wife and I certainly don’t see eye to eye on everything.
dissent formal (to disagree with an opinion or decision that is officially accepted): Just two of the members dissented from the decision.