plural noun
Chae·​tog·​na·​tha | \ kēˈtägnəthə \

Definition of Chaetognatha

: a phylum of small, slender marine animals comprising the arrow worms But the absence of a definite synapomorphy between Chaetognatha and any other metazoan taxon except Bilateria itself has cast the arrowworms into an enduring isolation.— Edward E. Ruppert et al., Invertebrate Zoology: A Functional Evolutionary Approach, 2004 — see also sagitta, spadella

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Other Words from Chaetognatha

chaetognathan \ -​thən \ adjective
chaetognathous \ -​thəs \ adjective

History and Etymology for Chaetognatha

New Latin, from chaet- + -gnatha

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Cite this Entry

“Chaetognatha.” Dictionary, Merriam-Webster, Accessed 29 Nov. 2021.

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