bookworm

The word 'bookworm' is a transparent compound formed from two native English elements. The literal sense, referring to an insect larva that bores through books, dates to the late 16th century, drawing on the ancient and widespread use of 'worm' for any small, destructive creature. The figurative, and now primary, sense of a keen and studious reader emerged in the mid-18th century by metaphorically comparing a person who devours books to the insect that literally consumes them. This semantic evolution perfectly illustrates how a concrete, sometimes negative, literal meaning can transform into a common, often mildly humorous, term for a human habit.

Structure: book (object) + worm (creature) - book: From Old English 'bōc', meaning a written document or volume. In this compound, it functions as a noun modifier specifying the object of association. - worm: From Old English 'wyrm', meaning a creeping or crawling animal, a serpent, or an insect larva. In this compound, it functions as the core noun, metaphorically describing a person or a literal pest.