What does "redhead" mean?

Redhead: (Zoöl.) (a) An American duck (Aythya Americana) highly esteemed as a game bird. It is closely allied to the canvasback, but is smaller and its head brighter red. Called also red-headed duck. American poachard, grayback, and fall duck. See Illust. under Poachard. (b) The red-headed woodpecker. See Woodpecker.

Additional senses

  1. 2.(Bot.) A kind of milkweed (Asclepias Curassavica) with red flowers. It is used in medicine.

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