Any of numerous usually free-swimming marine coelenterates of the class Scyphozoa, characteristically having a gelatinous, tentacled, often bell-shaped medusoid stage as the dominant phase of its life cycle.

• 水母,海蜇:大量的、经常自由游动的真水母类腔肠动物,胶质的、带有触须的、常为钟形的类水母体阶段是其生命循环中的主要形式。