Any of various invertebrates, as those of the phyla Annelida, Nematoda, Nemertea, or Platyhelminthes, having a long, flexible, rounded or flattened body, often without obvious appendages.
虫:几种无脊椎动物中的一种,如环节动物门、线虫类、纽形动物或扁形动物门,有长的、柔软的、圆的或扁平的身体,经常没有明显的附属肢体