Nemathelminthes
noun plural
Nem·a·thel·min·thes
| \ -ˌthel-ˈmin(t)-(ˌ)thēz
\
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Medical Definition of Nemathelminthes
in some classifications
: a phylum including the nematodes and horsehair worms and sometimes the acanthocephalans, rotifers, gastrotrichs, and minute marine organisms of a related class (Kinorhyncha) which are all more or less wormlike animals with a cylindrical unsegmented body covered by an ectoderm without cilia that secretes an external cuticle