The word pettifogging is often used to refer to trivial or petty behavior. In contrast, there are several antonyms that can be used to describe the opposite of pettifogging. Words such as serious, significant, substantial, and weighty all convey a sense of importance and significance. These antonyms suggest a level of importance and gravity that is not associated with petty behavior. In addition, words such as decisive, resolute, and determined convey a sense of purpose and commitment that is lacking in pettifogging behavior. So, while pettifogging behavior may be trivial and petty, there are many antonyms that can be used to describe the opposite.