What does echinococci mean?
Echinococci is the plural of echinococcus, a genus of minute parasitic tapeworms that pose a significant public-health concern worldwide. The adult worms live in the intestines of carnivores, most commonly dogs, wolves and foxes, and measure only a few millimetres in length despite their outsized impact. Their eggs, shed in the faeces of these hosts, can be accidentally ingested by humans through contaminated food, water or close contact with infected animals. Inside the human body, the parasites develop into larvae that form slow-growing, fluid-filled structures known as hydatid cysts, typically in the liver or lungs — a condition called echinococcosis or hydatid disease. Because the word is confined largely to medical, veterinary and epidemiological writing, it carries a formal, clinical register. Understanding echinococci matters chiefly because early infection is often symptomless, making prevention through deworming dogs and safe food handling especially important.
nounEchinococci is the plural of echinococcus, a genus of small parasitic tapeworms whose larval stage causes cystic disease (hydatid disease) in humans and other mammals.
- Plural of echinococcus: small tapeworms of the genus Echinococcus that infect the intestines of carnivores such as dogs and foxes.
- The larval stages of these tapeworms, which form hydatid cysts in the organs of intermediate hosts including humans and livestock.
"The veterinary surgeon explained that echinococci can pass from infected dogs to humans through contaminated food or water."
"Screening programmes have dramatically reduced the number of echinococci circulating among sheepdogs in the region."
"Once ingested, echinococci migrate from the intestine and settle in the liver or lungs, where they develop into slow-growing cysts."
This is itself a plural form (the singular is 'echinococcus'); it follows the Latin second-declension pattern seen in words like cactus → cacti.
"Several echinococci were identified during the post-mortem examination of the coyote."
A single echinococcus tapeworm is only a few millimetres long, yet its larvae can grow into fluid-filled hydatid cysts the size of a grapefruit inside a human liver.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of echinococci
The word derives from New Latin Echinococcus, the scientific genus name coined in the early nineteenth century from two Greek roots: echinos, meaning 'hedgehog' or 'spiny one', and kokkos, meaning 'berry' or 'grain', an allusion to the parasite's small, rounded form. The same Greek root echinos appears in other scientific coinages such as echinoderm ('spiny-skinned'), while kokkos underlies terms like coccyx and micrococcus. As a Latinised plural of a second-declension masculine noun, echinococcus becomes echinococci in the plural, following the pattern of words such as cactus and focus.
Related word forms
How echinococci is actually used
Strictly a technical term used in medicine, veterinary science and parasitology; it is almost never encountered in everyday conversation. In medical writing, 'echinococci' usually refers to the adult intestinal worms, while discussion of human disease typically centres on their larval forms and uses related terms such as 'hydatid cyst' or 'echinococcosis'.
Easily confused with echinococci
Echinodermata are marine animals such as starfish and sea urchins, whereas echinococci are parasitic tapeworms; both share the Greek root echinos ('spiny') but are otherwise unrelated.