Iris pseudacorus

from WordNet (r) 3.0 (2006)

Iris pseudacorus
    n 1: common yellow-flowered iris of Europe and North Africa,
         naturalized in United States and often cultivated [syn:
         {yellow iris}, {yellow flag}, {yellow water flag}, {Iris
         pseudacorus}]

from The Collaborative International Dictionary of English v.0.48

Water flag \Wa"ter flag`\ (Bot.)
   A European species of Iris ({Iris Pseudacorus}) having bright
   yellow flowers.
   [1913 Webster]

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