Quadrilatʹeral.
The four fortresses of Peschie’ra and Mantua on the Mincio, with Vero’na and Legna’go on the Ad’igë. Now demolished.
The Prussian Quadrilateral. The fortresses of Luxemburg, Coblentz, Sarrelouis, and Mayence.
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Entry taken from Dictionary of Phrase and Fable, edited by the Rev. E. Cobham Brewer, LL.D. and revised in 1895.