Definition of Chaetognatha in English:


plural noun

  • A small phylum of marine invertebrates that comprises the arrow worms.

    • ‘Also absent are the Chaetognatha (arrow-worms), which have been considered the basalmost branch of the Deuterostomia in the past, but are currently regarded by many as basal protostomes.’
    • ‘Also unresolved are the phylogenetic positions of Cycloneuralia, Chaetognatha, Gnathostomulida, Cycliophora, and Micrognathozoa.’
    • ‘Pelagic species were from the Chaetognatha, Cnidaria, Crustacea, Ctenophora, and Mollusca, and benthic species were from the Chordata, Crustacea, Mollusca, and Echinodermata.’
    • ‘Instead, Rouse's conclusion that ‘groups such as the Arthropoda, Brachiopoda, Chaetognatha, Ectoprocta, Gastrotricha, Phoronida may have lost a prototroch’ is totally gratuitous, and remains unaddressed by his own data.’
    • ‘Nielsen and Nielsen et al. come to generally comparable results, although sometimes the additional taxa Rotifera, Acanthocephala and Chaetognatha were included in Aschelminthes.’


Modern Latin (plural), from Greek khaitē ‘long hair’ + gnathos ‘jaw’.