An earworm is a tune that gets stuck in your head and plays again and again, even when you wish it would stop. It is not a real worm, and it is not in your ear. It is only a picture in language, as if a little creature had crawled in and would not leave. Short, easy, catchy songs do this most often: an advert, a chorus from the radio, a song from a shop. You can like the song and still call it an earworm; the point is that you did not choose to keep hearing it. The word is copied from German, which uses the same picture. Though actually, earworm can also mean a kind of baby moth that eats corn. “Ear” there is the ear of corn — the part we eat — not the ear on your head. That is a farm-pest meaning. In everyday talk, almost everyone who says earworm means the stuck song. A few older uses also treat earworm as another word for the insect earwig; that is uncommon now, and it is not what people mean in a chat about music.

洗腦歌。有人直譯成「耳蟲」，但台灣日常都說洗腦歌。