Lumbricus terrestris is a large, reddish worm species native to Europe, but now also widely distributed elsewhere around the world (along with several other lumbricids) due to human introductions. In some areas where it has been introduced, some people consider it to be a serious pest species since it is outcompeting native worms.
Through much of Europe, it is the largest naturally occurring species of earthworm, typically reaching 20 - 25 cm in length when extended (though in parts of southern Europe, the native species are much larger). In September 2012, a specimen was found in SW China measuring roughly 50 cm in length. It has an unusual habit of copulating on the surface at night, which makes it more visible than most other earthworms.
The term worm (pronounced /ˈwɜrm/) refers to an obsolete taxon (vermes) used by Carolus Linnaeus and Jean-Baptiste Lamarck for all non-arthropod invertebrate animals, and stems from the Old English word wyrm. Currently it is used to describe many different distantly related animals that typically have a long cylindrical tube-like body and no legs. Most animals called "worms" are invertebrates, but the term is also used for the amphibian caecilians and the slow worm Anguis, a legless burrowing lizard. Invertebrate animals commonly called "worms" include annelids (earthworms), nematodes (roundworms), platyhelminthes (flatworms), marine polychaete worms (bristle worms), marine nemertean worms ("bootlace worms"), marine Chaetognatha (arrow worms), priapulid worms, and insect larvae such as caterpillars, grubs, and maggots. Historical English-speaking cultures have used the (now deprecated) terms worm, Wurm, or wyrm to describe carnivorous reptiles ("serpents"), and the related mythical beasts dragons. The term worm can also be used as an insult or pejorative term used towards people to describe a cowardly or weak individual or individual seen as pitiable.