Definition of phosphorous in English:



  • 1Relating to or containing phosphorus.

    Compare with phosphoric
    • ‘Fig.6 shows the pair radial distribution functions between ions and the phosphorous and nitrogen atoms of the headgroup.’
    • ‘Lipid spots were identified using a standard phosphorous stain.’
    • ‘The methyl halide can be produced by reacting methanol with phosphorous halides, hydrogen halides, or, in the case of methyl chloride, thionyl chloride.’
    • ‘The on-call Explosive Ordnance Disposal (bomb-disposal) diver was CPO Diver Andy Carss, who had earlier that day safely disposed of a phosphorous flare found on a beach in Norfolk - one of six such incidents this week.’
    • ‘For example, in the iron and steel industry, the search for methods to neutralize the deleterious effects of phosphorous iron ore not only produced technological change, it also made the range of useable ore inputs endogenous.’
    1. 1.1Chemistry Of phosphorus with a valency of three.
      • ‘For example, two phosphorus atoms, each having a valence of 3, making a total valence of 6, require, in order to combine with O, whose valence is 2, three atoms of O, which make the valence of 6.’
      • ‘The word phosphorous is the adjectival form of the P3+ valency.’
    2. 1.2Phosphorescent.
      • ‘Edoux and Soulezet collected some of the phosphorous substance.’
      • ‘A phosphorous mineral glows on its own, but just a little bit.’


The correct spelling for the chemical element is phosphorus, while the adjective meaning ‘relating to or containing phosphorus’ is spelled phosphorous. A common mistake is to use the spelling phosphorous for the noun as well as the adjective