The phrase "haddest oneself" is commonly used as an outdated version of the word "behave." There are plenty of synonyms that can be used instead of "haddest oneself," including words like "act," "conduct," "behave oneself," "carry oneself," "perform," "comport oneself," and "conduct oneself." These words all carry a similar meaning to "haddest oneself" but are more commonly used in modern language. Proper behavior and conduct are essential in everyday life, so having a full understanding of these words' meanings and synonyms can help you communicate effectively and express your thoughts precisely.