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Related to pyrophoric: Pyrophoric iron, Organic peroxide


1. Spontaneously igniting in air.
2. Producing sparks by friction.

[From pyrophorus, substance that ignites spontaneously : from Greek purophoros, fire-bearing : puro-, pyro- + -phoros, -phorous.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˌpaɪrəʊˈfɒrɪk) or


1. (Chemistry) (of a chemical) igniting spontaneously on contact with air
2. (General Physics) (of an alloy) producing sparks when struck or scraped: lighter flints are made of pyrophoric alloy.
[C19: from New Latin pyrophorus, from Greek purophoros fire-bearing, from pur fire + pherein to bear]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌpaɪ rəˈfɔr ɪk, -ˈfɒr-)

capable of igniting spontaneously in air.
[1830–40; < Greek pyrophór(os) fire-bearing]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
There are two possible sources of ignition - static electricity generated in the hose being used for pumping or the presence of pyrophoric substances in the tank, which can spontaneously combust on contact with air.
However, these bring different challenges as they are energetic and extremely air and moisture sensitive, and often necessitate the use of pyrophoric and short shelf-life reagents.
The tank had been emptied and flushed as per standard operating procedures, and was in the initial stages of venting to remove pyrophoric material which likely became flammable, causing the fire, it added.
Some materials are pyrophoric (they ignite easily when coming into contact with air).
for REE imports are free for lanthanum oxides and other oxides, and range from 3.7% for lanthanum carbonates, other carbonates, and other REE compounds; 5% for scandium and yttrium whether or not mixed or intermixed; 5.5% for cerium compounds such as oxides; and 5.9% for ferrocerium and other pyrophoric allies.
Gregite ([Fe.sub.3] Iron Sulfide Corrosion Products: [S.sub.4]) Pyrite (Fe[S.sub.2]) (i) Pyrophoric iron sulfide Marcasite (Fe[S.sub.2]) (pyrrhotite-FeS) results from Mackinawite (Fe[S.sub.0.9]) the corrosive action of sulfur Pyrrhotite ([Fe.sub.7] or sulfur compounds [S.sub.8]) ([H.sub.2]S) on the iron (steel) and moisture.
These materials are not toxic or pyrophoric, and their cost is lower than previous materials used in CdSe QD synthesis.
TEA-TAB is pyrophoric, meaning it spontaneously catches fire when exposed to your run of the mill air, a decidedly human-unfriendly feature.
RIYADH: Saudi Aramco's Haradh Gas Plant has pioneered the use of Concrete Canvas (CC) in the construction of a pyrophoric treatment area, the works for which were carried out by Saudi-based Freih Bin Owaidha Al Qahtani Sons Co Ltd (FOQSCO).
A chemical that is pyrophoric (UN GHS Hazard H250) is also a flammable liquid (UN GHS Hazard H228).
It's not truly pyrophoric; that distinction belongs to much lighter methyl-metallics like dimethylzinc and trimethylaluminum.