hydrozoan /ˌhaɪdrəʊˈzəʊən/

• 1.  

  N（名词） any colonial or solitary coelenterate of the class Hydrozoa, which includes the hydra, Portuguese man-of-war, and the sertularians 水螅类
• 2.  

  ADJ（形容词） of, relating to, or belonging to the Hydrozoa 水螅类的