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Portuguese man-of-war

noun
  1. any of several large, oceanic hydrozoans of the genus Physalia, having a large, bladderlike structure with a saillike crest by which they are buoyed up and from which dangle tentacles with stinging cells.

Origin of Portuguese man-of-war

First recorded in 1700–10
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for portuguese man-of-war

Portuguese man-of-war

noun
  1. any of several large complex colonial hydrozoans of the genus Physalia, esp P. physalis, having an aerial float and long stinging tentacles: order SiphonophoraSometimes shortened to: man-of-war
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