From Longman Dictionary of Contemporary Englishon/onto the defensiveon/onto the defensiveCRITICIZEbehaving in a way that shows that you think that someone is criticizing you even if they are not In his presence, she was constantly on the defensive. → defensive
Examples from the Corpus
on/onto the defensive• It was the only time in her life that she had noticed her maternal grandmother at a disadvantage, on the defensive.• This immediately puts the farmer on the defensive and reinforces the public's perception of them as a complaining, dissatisfied group.• The conference, held in a Protestant church, found Daley and his group on the defensive.• Motta always put him on the defensive.• The industry is on the defensive in Congress, in courts across the nation and in the war for public opinion.• He was tense now - on the defensive. 