blue flag


Definition of blue flag

: a blue-flowered iris especially : a common iris (Iris versicolor) chiefly of the eastern U.S. with a root formerly used medicinally

First Known Use of blue flag

1732, in the meaning defined above

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The first known use of blue flag was in 1732

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Cite this Entry

“Blue flag.” Dictionary, Merriam-Webster, Accessed 18 Jan. 2021.

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More Definitions for blue flag

blue flag

\ -ˈflag How to pronounce blue flag (audio) \

Medical Definition of blue flag

1 : either of two common blue-flowered irises (Iris versicolor and I. virginica) of the eastern and central United States with rhizomes formerly used medicinally as a cathartic and emetic
2 : the dried rhizome of a blue flag

called also blue flag root

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