#seaweed  plant growing in the sea, especially marine algae
  supertype:  #alga__algae  primitive chlorophyll-containing mainly aquatic eukaryotic organisms lacking true stems and roots and leaves
  subtype:  #arame  an edilbe seaweed with a mild flavor
  subtype:  #wrack  dried seaweed especially that cast ashore
  subtype:  #seagrass  any of various seaweeds that grow underwater in shallow beds
  subtype:  #sea_wrack__seawrack__wrack  growth of marine vegetation especially of the large forms such as rockweeds and kelp
  subtype:  #sea_tang__seatang__tang  any of various coarse seaweeds

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