Prole drift

The proletariat (/ˌproʊlᵻˈtɛəri.ət/ from Latin proletarius) is the class of wage-earners in a capitalist society whose only possession of significant material value is their labor-power (their ability to work). A member of such a class is a proletarian.

The proletarii constituted a social class of Roman citizens owning little or no property. The origin of the name is presumably linked with the census, which Roman authorities conducted every five years to produce a register of citizens and their property from which their military duties and voting privileges could be determined. For citizens with property valued 11,000 asses or less, which was below the lowest census for military service, their children—proles (from Latin prōlēs, "offspring")—were listed instead of their property; hence, the name proletarius, "the one who produces offspring". The only contribution of a proletarius to the Roman society was seen in his ability to raise children, the future Roman citizens who can colonize new territories conquered by the Roman Republic and later by the Roman Empire. The citizens who had no property of significance were called capite censi because they were "persons registered not as to their property...but simply as to their existence as living individuals, primarily as heads (caput) of a family."

...
Wikipedia