From Longman Dictionary of Contemporary Englishknow betterknow bettera)SENSIBLEto be wise or experienced enough not to do somethingIt’s just prejudice from educated people who should know better.Eva knew better than to interrupt one of Mark’s jokes.b)KNOW somethingto know or think you know more than someone elseEveryone thought it was an accident. Only Dan knew better. →know
Examples from the Corpus
knew better than to• And Jessamy knew better than toargue with him when he used that particular tone of voice.• They knew better than to be left out.• The photograph became a powerfulpresence in my life, so much so that Kipknew better than tocomment.• I knew better than to go in.• Now Ralph knew better than to let his hopes swell but still they surged like a rain-drunk river.• Or, if they did, they knew better than toremonstrate with the grim-faced man behind her.• Charlie would understand what I meant, but I knew better than to speak to him about Frank.• She knew better than to walk around the front of the house.