Marquis
Marquis , noun
[French marquis, Old French markis, marchis, Late Latin marchensis; of German origin; compare German mark bound, border, march, Old High German marcha. See March border, and compare Marchioness, Marquee, Marquess.]
A nobleman in England, France, and Germany, of a rank next below that of duke. Originally, the marquis was an officer whose duty was to guard the marches or frontiers of the kingdom. The office has ceased, and the name is now a mere title conferred by patent.