What is a nematode worm (Trichocephalus dispar) often found parasitic in the human intestine. Its body is thickened posteriorly, but is very long and threadlike anteriorly called?

whipworm — A nematode worm (Trichocephalus dispar) often found parasitic in the human intestine. Its body is thickened posteriorly, but is very long and threadlike anteriorly. (Webster's 1913.)

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