What does filaria mean?
A filaria is any of a group of long, thread-like parasitic roundworms belonging to the superfamily Filarioidea, whose name derives directly from the Latin word for thread. These worms are transmitted to humans and other mammals by blood-feeding insects, notably mosquitoes and blackflies, and they spend much of their life cycle within the host's lymphatic system, skin, or bloodstream. Some species cause serious chronic diseases: Wuchereria bancrofti can lead to lymphatic filariasis, commonly known as elephantiasis, while Onchocerca volvulus is responsible for river blindness. In medical and scientific contexts the singular form is relatively uncommon; writers more often use the plural 'filariae', the adjective 'filarial', or the disease term 'filariasis'. Because global health campaigns have made great strides against these parasites, the word also appears frequently in tropical medicine and public health literature.
nounA slender, thread-like parasitic roundworm of the family Filariidae, transmitted to humans and other animals by blood-feeding insects and capable of causing diseases such as elephantiasis and river blindness.
- A thread-like parasitic nematode worm of the family Filariidae, especially one infecting humans or animals.
- (In older or collective use) The condition or infestation caused by such worms; now usually termed filariasis.
"The patient's lymphatic swelling was traced to an adult filaria lodged in the lymphatic vessels."
"Blood smears revealed microfilariae of the filaria Wuchereria bancrofti."
"Mass drug administration programmes have dramatically reduced filaria transmission across affected regions."
Standard Latinate plural, pronounced /fɪˈlɛəri.iː/. Common in medical and zoological writing; the anglicized informal plural 'filaria worms' also occurs.
"Microscopic examination detected circulating filariae in the patient's night-time blood sample."
The name literally means 'thread' in Latin — fitting for a worm so thin it can weave through the human lymphatic system undetected for years.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of filaria
The word 'filaria' comes from New Latin, formed from Latin 'filum', meaning 'thread', with the diminutive-style suffix '-aria', reflecting the worm's remarkably slender shape. It was adopted into scientific nomenclature as the zoological genus name in the early nineteenth century. The same Latin root gives English 'filament', 'filiform', and 'profile', all of which carry a sense of thinness or thread-like structure.
Related word forms
How filaria is actually used
A technical term used chiefly in medicine, parasitology, and tropical public health; rare in everyday speech. In modern clinical writing, 'filarial worm' is common when referring generally, and 'filariasis' is preferred for the disease the worms cause.
Easily confused with filaria
Though both are parasitic diseases spread by biting insects and the two words sound alike, malaria is caused by a protozoan parasite, whereas a filaria is itself a thread-like worm.