(A ). An Austrian soldier. So called because he wears a white coat. Similarly, an English soldier is called a red-coat. In old Rome, ad saga ire meant to “become a soldier,” and tumere sagum to enlist, from the sagum or military cloak worn by the soldier, in contradistinction to the toga worn by the citizen in times of peace.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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