Definition of pyrophoric in English:

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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.
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'.

Words that rhyme with pyrophoric

aleatoric, allegoric, anaphoric, camphoric, categoric, choric, Doric, euphoric, historic, metaphoric, meteoric, phantasmagoric, phosphoric, semaphoric, sophomoric, theophoric, Warwick, Yorick

For editors and proofreaders

Line breaks: pyro|phor¦ic

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