Any of various primitive aquaticvertebrates of the class Cyclostomata, lacking jaws and including the lampreys and hagfishes.
鳗类，鳗：无颚的各种原始水生圆口纲脊椎动物中的一种，包括七鳃鳗和盲鳗。
2
Any of numerous cold-blooded aquaticvertebrates of the superclass Pisces, characteristically having fins, gills, and a streamlined body and including specifically.