A jacket of warm material. Many of these things were supplied to soldiers in the Civil War.

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1805.  I got up, and found that my waumus was bloody, which I had not observed before.—Dying Confession of Charles Cunningham: Lancaster (Pa.) Intelligencer, Nov. 12.

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1854.  He was attired with a red flannel ‘wamus,’ a leathern belt girt around his waist, deer-skin leggins and moccasins, and a white felt hat that run up to a peak.—H. H. Riley, ‘Puddleford,’ p. 14 (N.Y.).

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