In Somersetshire bunting means sifting flour. Sieves were at one time made of a strong gauzy woollen cloth, which being tough and capable of resisting wear, was found suitable for flags, and now has changed its reference from sieves to flags. A “bunt-mill” is a machine for sifting corn.
“Not unlike ... a baker's bunt, when he separates the flour from the bran.” —Stedman.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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