pyrolysis

1 of 2

noun

py·​rol·​y·​sis pī-ˈrä-lə-səs How to pronounce pyrolysis (audio)
: chemical change brought about by the action of heat
pyrolytic
ˌpī-rə-ˈli-tik How to pronounce pyrolysis (audio)
adjective
pyrolytically
ˌpī-rə-ˈli-ti-k(ə-)lē How to pronounce pyrolysis (audio)
adverb

pyrolytic

2 of 2

adjective

py·​ro·​lyt·​ic ¦pīrə¦litik How to pronounce pyrolytic (audio)
: of, relating to, or produced by means of pyrolysis
pyrolytically
-tə̇k(ə)lē How to pronounce pyrolytic (audio)
adverb

Examples of pyrolysis in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
While most fires utilize the combustion process, biochar is created via pyrolysis, which only occurs in the absence of oxygen. — Lauren Landers, Better Homes & Gardens, 21 Apr. 2026 As the capsule dipped into the atmosphere, internal layers became scorching hot through a process called pyrolysis, trapping gas. — Catherina Gioino, Fortune, 11 Apr. 2026 The main method, a process known as pyrolysis, has long been regulated as incineration by the Clean Air Act. — ABC News, 15 Apr. 2026 The group protested Thursday afternoon against the major plastic recycling facility that is testing a method called pyrolysis. — Bryant Reed, CBS News, 14 May 2026 See All Example Sentences for pyrolysis

Word History

Etymology

Noun

New Latin

Adjective

pyr- + -lytic

First Known Use

Noun

circa 1890, in the meaning defined above

Time Traveler
The first known use of pyrolysis was circa 1890

Rhymes for pyrolysis

See All Rhymes for pyrolysis

Browse Nearby Words

pyrolysate
pyrolysis
pyrolytic
See all Nearby Words

Cite this Entry

“Pyrolysis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pyrolysis. Accessed 7 Jul. 2026.

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Medical Definition

pyrolysis

noun
py·​rol·​y·​sis pī-ˈräl-ə-səs How to pronounce pyrolysis (audio)
plural pyrolyses -ˌsēz How to pronounce pyrolysis (audio)
: chemical change brought about by the action of heat
pyrolytic
ˌpī-rə-ˈlit-ik How to pronounce pyrolysis (audio)
adjective

More from Merriam-Webster on pyrolysis

Britannica.com: Encyclopedia article about pyrolysis

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