The Collaborative International Dictionary of English v.0.48:

Ascarid \As"ca*rid\, n.; pl. Ascaridesor Ascarids. [NL.
   ascaris, fr. Gr. ?.] (Zool.)
   A parasitic nematoid worm, especially the roundworm, Ascaris
   lumbricoides, often occurring in the human intestine, and
   allied species found in domestic animals; also commonly
   applied to the pinworm (Oxyuris), often troublesome to
   children and aged persons.
   [1913 Webster]