(French, á cheval). Troops are arranged á cheval when they command two roads, as Wellington's army at Waterloo, which, being at the apex of two roads, commanded that between Charleroi and Brussels, as well as that to Mons.
“The Western Powers will assuredly never permit Russia to place herself again á cheval between the Ottoman empire and Persia.” —The Times.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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