«زَيِّ الطَّبْلْ مَنْفُوخْ عَلَى الْفَارِغْ»

A drum looks swollen and full, yet its body is hollow; blown up over emptiness, it promises more than it holds. The saying can be heard two ways: the drum is inflated around nothing, or it is puffed up for no reason at all. Both point to hollowness behind an inflated surface, not mainly to noise.

Applied to people, it targets someone who acts lofty and meets others with a stern, sullen face when nothing warrants it. The criticism is that the pride is baseless: no merit, standing, or genuine cause lies behind the person's grand and forbidding manner. It is a disparaging judgment.

Use it to deflate someone who swells with importance and treats others coldly without any cause to justify it. It fits informal, often ironic remarks about such behavior; said directly to a person, it can easily come across as an insult.