red dog

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red dog (countable and uncountable, plural red dogs)

1. (countable, US, American football) A blitz.
2. (uncountable) The lowest grade of flour in milling, secured largely from the germ or embryo and adjacent parts, and mainly useful as animal feed.
   • 1918, Alonzo Englebert Taylor, War Bread‎^[1], New York: Macmillan, page 75:

     This fraction of grain offal contains a number of over-lapping sub-fractions, which are known in the trade as red-dog, shorts, middlings, and bran. A portion of the red-dog is contained in the lowest grade of straight flour.

3. (uncountable) Coal slag.
4. (uncountable, informal) Prickly heat; miliaria.
5. Used other than figuratively or idiomatically: see red,‎ dog.

red dog (third-person singular simple present red dogs, present participle red dogging, simple past and past participle red dogged)

1. (US, American football) To blitz.

red dog

1. A card game in which players bet on the next card to appear.

• Dodger, dodger