filaria fi·lar·i·a (fə-lâr'ē-ə)
n. pl. fi·lar·i·ae (-ē-ē')
Any of various threadlike nematode worms of the superfamily Filarioidea parasitic in vertebrates and often transmitted as larvae by biting insects. The adult form lives in the blood and lymphatic tissues, causing inflammation and obstruction that can lead to elephantiasis.
A genus of nematodes no longer in taxonomic use and whose members are now classified in the family Onchocercidae.