roundworm

An intestinal parasitic worm, Ascaris lumbricoides, several inches long, infesting the human intestine: distinguished from the similar but much smaller pinworms or threadworms, and from the larger and more formidable flatworms, jointworms, or tapes.

Hence Any member of the class Nematelmintha; a nematoid worm: distinguished from cestoid and trematoid worms, or tapeworms and flukes.

A nematoid worm.

An invertebrate animal of the phylum Nematoda. Many species of roundworms are parasites.

infections of the skin or nails caused by fungi and appearing as itching circular patches

unsegmented worms with elongated rounded body pointed at both ends; mostly free-living but some are parasitic