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pyrophoric Syllabification: py·ro·phor·ic
Pronunciation: /ˌpīrōˈfôrik/

Definition of pyrophoric in English:


1Liable to ignite spontaneously on exposure to air.
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

Definition of pyrophoric in:

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