Definition
To act "pompously" means to behave in a self-important and arrogant manner. It involves displaying an exaggerated sense of one's own importance and superiority. Think of it as the opposite of being humble or modest. A pompous person often uses overly formal language and acts as if they are better than everyone else. It's like Draco Malfoy bragging about his family's wealth and status. It's generally seen as off-putting.