Chaetognatha

plural noun

Chae·​tog·​na·​tha

kēˈtägnəthə

: 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

chaetognathan

-thən

adjective

chaetognathous

-thəs

adjective

Word History

Etymology

New Latin, from chaet- + -gnatha

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