A thick blanket used by the Indians of the North-West.

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1839.  We had Mackinaw-blankets, stretched upon balsam branches, to recline upon.—C. F. Hoffman, ‘Wild Scenes,’ i. 113–4 (Lond.).

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1851.  My “Mackinaw,” a great favorite—for it makes my bed by night, and my great-coat on other occasions.—Mayne Reid, ‘The Scalp Hunters,’ p. 17. (N.E.D.)

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1856.  My physician—that’s me—strongly recommended a tent, a soft plank, and a Mackinaw blanket.Putnam’s Mag., viii. 384/2 (Oct.).

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1857.  Mac was making a variety of contortions between heaven and a mackinaw.San Francisco Call, Jan. 29.

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