"Pettier" is a term that defines behavior as being small-minded, paltry, or unimportant. Synonyms for the word "pettier" include more insignificant, childish, shallow, narrow-minded, and trivial. Other synonyms for "pettier" may include frivolous, petty-minded, and snide. These terms all refer to behavior that is small or insignificant, usually involving unimportant or trivial matters. It is important to remember that these synonyms vary in degree, with some being stronger than others, but they all refer to an attitude or behavior that is beneath someone. When someone acts petty, their actions and words are often perceived as immature and lacking in respect for others.