Definition of pyrophoric in English:


Line breaks: pyro|phor¦ic
Pronunciation: /ˌpʌɪrə(ʊ)ˈfɒrɪk


  • 1Liable to ignite spontaneously on exposure to air: several boranes are pyrophoric and toxic
    More example sentences
    • It is pyrophoric, burning spontaneously on impact, and extremely dense.
    • We have a lot of pyrophoric substances in an organic chemistry lab - things that burst into flame when they encounter normal air.
    • In addition to the radioactivity, DU is chemically toxic, pyrophoric and usually spreads aerolisized particles over a large area on impact.
  • 1.1(Of an alloy) emitting sparks when scratched or struck.
    More example sentences
    • One of the oldest uses for praseodymium is in the manufacture of misch metal, a pyrophoric metal.
    • The Army and other pyrophoric uranium munitions NRC licensees should admit the quantity of UO3 vapor produced by such weapons.
    • Aside from being very dense and pyrophoric, depleted uranium shells also have a nasty tendency to vaporise.


mid 19th century: from modern Latin pyrophorus, from Greek purophoros 'fire-bearing', from pur 'fire' + pherein 'to bear'.

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