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phosphorous Syllabification: phos·pho·rous
Pronunciation: /ˈfäsfərəs/ /fäsˈfôrəs/

Definition of phosphorous in English:


1Relating to or containing phosphorus. Compare with phosphoric.
Example sentences
  • The methyl halide can be produced by reacting methanol with phosphorous halides, hydrogen halides, or, in the case of methyl chloride, thionyl chloride.
  • Lipid spots were identified using a standard phosphorous stain.
  • 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 Chemistry Of phosphorus with a valence of three.
Example sentences
  • 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.
Example sentences
  • A phosphorous mineral glows on its own, but just a little bit.
  • Edoux and Soulezet collected some of the phosphorous substance.


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

Words that rhyme with phosphorous


Definition of phosphorous in:

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