Source : Webster's Revised Unabridged Dictionary (1913)

Yoncopin \Yon"co*pin\, n. [Perhaps corrupted from Illinois
   micoupena, Chippewa makopin, the American lotus.] (Bot.)
   A local name in parts of the Mississippi Valley for the
   American lotus ({Nelumbo lutea}).

Nelumbo \Ne*lum"bo\, n. [Ceylonese word.] (Bot.)
   A genus of great water lilies. The North American species is
   {Nelumbo lutea}, the Asiatic is the sacred lotus, {N.
   speciosa}. [Written also {Nelumbium}.]

Source : WordNet®

Nelumbo lutea
     n : water lily of eastern North America having pale yellow
         blossoms and edible globular nutlike seeds [syn: {water
         chinquapin}, {American lotus}, {yanquapin}]