1. ヒドロ虫と鉢虫類の動物の生殖再生形態を作る、通常は海洋性で自由遊泳性の非常に多い腔腸動物類各種(any of numerous usually marine and free-swimming coelenterates that constitute the sexually reproductive forms of hydrozoans and scyphozoans)
2. 嚢のような浮袋と刺す触手を持つ大型クダクラゲ(large siphonophore having a bladderlike float and stinging tentacles)