Uncourteousness is a behavior or attitude that is rude, impolite or discourteous. Some synonyms for this word include rudeness, impoliteness, disrespect, discourtesy, incivility, and insolence. Other related words to describe this type of behavior include brusqueness, abrasiveness, and hostility. These words suggest an unpleasant demeanor or attitude that lacks the basic social skills necessary to communicate effectively. It is important to be aware of these synonyms and their usage, as they may come in handy in situations where being polite and respectful is crucial in social settings or professional environments.