To kvetch is to keep complaining in a small, ongoing way — not a big angry protest, but the kind of moaning that never quite stops. You kvetch about the weather, the coffee, the queue, your back. In American English, especially Jewish American talk, it is a familiar, slightly comic word; it still feels Yiddish in the mouth. As a noun, a kvetch is either the complaint itself or the person who is always doing it. People often say it with a half-smile, though actually if you call someone a kvetch to their face it can sting. It is informal. You would not put it in a school essay. It sits closer to “whine” or “gripe” than to “protest”.

碎碎念、發牢騷（美式口語，帶意第緒語味道；台灣沒有對等的外來詞）