Bookworm is a general name for any insect that is said to bore through books.[1][2]
The damage to books that is commonly attributed to "bookworms" is often caused by the larvae of various types of insects, including beetles, moths, and cockroaches, which may bore or chew through books seeking food. The damage is not caused by any species of worm. Some such larvae exhibit a superficial resemblance to worms and are the likely inspiration for the term, though they are not true worms. In other cases, termites, carpenter ants, and woodboring beetles will first infest wooden bookshelves and later feed on books placed upon the shelves, attracted by the wood-pulp paper used in most commercial book production.
True book-borers are uncommon. The primary food sources for many "bookworms" are the leather or cloth bindings of a book, the glue used in the binding process, or molds and fungi that grow on or inside books. When the pages themselves are attacked, a gradual encroachment across the surface of one page or a small number of pages is typical, rather than the boring of holes through the entire book.[3]
The term has come to have a second, idiomatic meaning of a bibliophile, who reads a great deal or to perceived excess: someone who devours books metaphorically.
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