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lungworm lung·worm (lŭng'wûrm')
Any of various nematode worms, especially of the family Metastrongylidae, that are parasitic in the lungs of mammals.
any of the parasitic worms of the superfamily Metastrongyloidea (class Nematoda, phylum Aschelminthes) that infest the lungs and air passages of mammals, including dolphins and whales. Examples include those of the genus Metastrongylus that live in pigs, and those of the genus Dictyocaulus that live in sheep and cattle. Many species of lungworms are of veterinary importance. Members of the genus Angiostrongylus, normally occurring as parasites in rats, are known to be pathogenic in humans. The life cycle of lungworms can be direct or involve intermediate hosts, such as snails and slugs. Lungworms should not be confused with lung flukes, such as those of the genus Paragonimus, which are trematodes.