Definition of residuum in English:



  • 1technical A chemical residue.

    • ‘After evaluation of the residuum and comparison with a threshold value, a fault signal is generated when the residuum reaches the threshold value.’
    • ‘The barite ore is massive and occurs within residuum derived from carbonate units.’
    • ‘But figuring out exactly how to regenerate ammonia borane from the residuum left after hydrogen has been extracted remains a stumbling block.’
    • ‘Type I peridotites are interpreted to be the residua remaining after extraction of a partial melt.’
    • ‘These soils are moderately deep to deep, well-drained loam or silt loam surface soils with loam or silty clay loam subsoils, formed primarily in sandstone residuum.’
    remainder, remaining part, part leftover, rest, remnant, remnants
    View synonyms
  • 2Sociology
    A class of society that is unemployed and without privileges or opportunities.

    ‘the urban residuum’
    • ‘There has always been a problem of classification in treatments of this social residuum; that of distinguishing between the worthy and unworthy poor.’
    • ‘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.’
    • ‘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.’
    • ‘Though the residuum is in one sense a social category, the concept implies that the group stands outside society and resists easy categorization.’


Late 17th century: from Latin, neuter of residuus remaining, from the verb residere.