Word Study
chaetognath
CIDE DICTIONARY
chaetognath, n.
any worm of the Chaetognatha; transparent marine worm with horizontal lateral and caudal fins and a row of movable curved spines at each side of the mouth. [WordNet 1.5]
OXFORD DICTIONARY
chaetognath, n. any dart-shaped worm of the phylum Chaetognatha, usu. living among marine plankton, and having a head with external thorny teeth.
Etymology
mod.L Chaetognatha f. Gk khaite long hair + gnathos jaw
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