malacopoda

from The Century Dictionary.

• noun A name given by E. R. Lankester to a grade of Gnathopoda (or Arthropoda) containing only the class Peripatidea, which itself consists of the single genus Peripatus, thus contrasted with a grade or series Condylopoda, including all other crustaceans, insects, etc.

from the GNU version of the Collaborative International Dictionary of English.

• proper noun plural (Zoöl.) A class of air-breathing Arthropoda; -- called also Protracheata, and Onychophora.