residuum
/rɪˈzɪdjʊəm
/noun (plural residua /rɪˈzɪdjʊə/)
1 technical A chemical residue.But figuring out exactly how to regenerate ammonia borane from the residuum left after hydrogen has been extracted remains a stumbling block....
- The barite ore is massive and occurs within residuum derived from carbonate units.
- Type I peridotites are interpreted to be the residua remaining after extraction of a partial melt.
2 Sociology A class of society that is unemployed and without privileges or opportunities: the urban residuum...
- Examples would be vagrants, skid-row alcoholics, the unemployed or casually employed residuum, youth adopting a deviant cultural style, ethnic minorities, gays, prostitutes and radical political organizations.
- Whereas the incorporation of the working class modified their systematic resentment at policing, police conflict with the residuum at the base of the social hierarchy remained.
- Though the residuum is in one sense a social category, the concept implies that the group stands outside society and resists easy categorization.
Origin
Late 17th century: from Latin, neuter of residuus 'remaining', from the verb residere.