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cyclostome

/ˈsaɪkloʊstoʊm/

Jawless fish with a round, sucker-like mouth

From Greek cyclo (circle) + Greek stome (mouth).

noun
adjective
cyclo
Ancient Greek
κύκλος (kýklos)
Circle, wheel, or ring
New Latin / scientific combining form
cyclo-
A combining form meaning circular or ring-shaped
English
cyclo-
Used in biological compounds, including cyclostome
stome
Ancient Greek
στόμα (stóma)
Mouth or opening
New Latin / scientific combining form
-stoma
A combining element meaning mouth
English
-stome
A biological combining form referring to a mouth or mouth-like opening
Combined
Cyclostomata / cyclostome
Scientific formation combining cyclo-, circular, with -stoma, mouth; literally a circular-mouthed animal
New Latin
Cyclostomata
Taxonomic name for organisms characterized by a round mouth
French
cyclostome
Biological term inherited or adapted from the taxonomic form
English
cyclostome
A jawless fish such as a lamprey or hagfish; also used in other biological classifications
Modern English
cyclostome

Picture a lamprey: a long, eel-like fish whose mouth looks less like a fish’s mouth than a living suction cup lined with teeth. That visual gave zoologists the name Cyclostomata, built from Greek kýklos, “circle,” and stóma, “mouth”—so the animal is, in effect, a “round-mouth.” The mouth-part has an impressive family tree: stoma also appears in stomatology, the study of the mouth, while cyclo- turns up in cycle and cyclic, words that still carry the idea of something moving in a ring. In 19th-century zoology, cyclostome usually grouped lampreys and hagfish as primitive jawless fishes, although scientists later argued over whether the group was a natural evolutionary unit; molecular evidence has since strongly supported their shared ancestry. The useful picture to remember is simple: a cyclostome is a fish whose mouth is built like a circle rather than a hinged jaw.

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