Any worm of the Chaetognatha,transparent marine worm with horizontal lateral and caudal fins and a row of movable curved spines at each side of the mouth.

• 毛颚类动物的蠕虫，透明的海生蠕虫，侧部水平，有尾鳍，嘴巴每侧有可卷曲活动的一排棘刺。