n.; pl.Ascarides r Ascarids. [ NL. ascaris, fr. Gr. &unr_;. ] (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 ]