earworm

The modern, psychological sense of 'earworm' is a calque, or loan translation, of the German word 'Ohrwurm', which emerged in the late 20th century. It is a vivid metaphorical compound where 'ear' represents the faculty of hearing and internal perception, while 'worm' conveys the idea of something burrowing in and being difficult to dislodge. This parallels the older, literal entomological use of the term from the late 19th century, which describes insect larvae that infest the ears of cereal crops. The word's logic hinges on the shared concept of an unwelcome, persistent invader, whether it be a physical pest in a plant's 'ear' (the seed-bearing head) or a cognitive pest in the human mind.

Structure: ear + worm ear: Old English 'ēare', of Germanic origin; related to Dutch 'oor' and German 'Ohr'. Denotes the organ of hearing or, metaphorically, attention. worm: Old English 'wyrm', meaning a serpent, dragon, or creeping invertebrate; of Germanic origin.