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canvasback vs. redhead

canvasback
[kan-vuhs-bak] / ˈkæn vəsˌbæk /

noun

canvasbacks, plural canvasback plural

  1. a North American wild duck, Aythya valisineria, the male of which has a whitish back and a reddish-brown head and neck.

redhead
[red-hed] / ˈrɛdˌhɛd /

noun

  1. a person having red hair.

  2. an American diving duck, Aythya americana, the male of which has a bright chestnut-red head.