slave [ME] Our word slave was shortened from early French esclave in the Middle Ages. In medieval Latin the equivalent form sclavus is identical with Sclavus, the source of Slav. The Slavic peoples of eastern and central Europe had been conquered and reduced to a servile state during the 9th century. Wage slaves is a term used in the English translation of the Communist Manifesto of 1848 by Karl Marx and Friedrich Engels.