If someone is flippant, they treat a serious matter as if it were small — a joke, a shrug, a clever line — when other people think it deserves care. A flippant remark is not always loud or rude. It can be smooth and smiling, which is why it stings: it says, without quite saying so, that the other person's worry is not worth the time. The word is a bit formal and usually critical. You will hear it from teachers, parents, and in writing about manners. Among friends, people more often say you are not taking it seriously, or that you are being too casual. Flippant is not the same as cheerful, and not the same as honest. You can be honest and still gentle; flippant skips the gentleness. It is also not the same as sarcastic, though the two can travel together. Sarcasm often cuts on purpose. Flippant may not mean to cut — it just will not sit still with the weight of the moment. Who uses it: adults judging tone, more than children naming a feeling.