plural noun

• An order of colonial marine coelenterates that includes the Portuguese man-of-war, having a float or swimming bell for drifting or swimming on the open sea.

  ‘These creatures are probably relatives of the Siphonophora, an order of colonial cnidarians that includes the venomous ‘Portuguese man-o-war’.’

  More example sentences

  • ‘Jones' last publication on the subject of marine life was on the morphology and relationships of the Siphonophora.’
  • ‘The Portuguese man-of-war is actually any of various invertebrate, jelly-like marine animals of the family Siphonophora.’