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Synonyms

soot

American  
[soot, soot] / sʊt, sut /

noun

  1. a black, carbonaceous substance produced during incomplete combustion of coal, wood, oil, etc., rising in fine particles and adhering to the sides of the chimney or pipe conveying the smoke: also conveyed in the atmosphere to other locations.

verb (used with object)

  1. to mark, cover, or treat with soot.

soot British  
/ sʊt /

noun

  1. finely divided carbon deposited from flames during the incomplete combustion of organic substances such as coal

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. (tr) to cover with soot

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
soot Scientific  
/ st /

  1. A black, powdery substance that consists mainly of carbon and is formed through the incomplete combustion of wood, coal, diesel oil, or other materials. Because it absorbs energy from sunlight rather than reflecting it, soot is believed to be a cause of global warming, especially when it settles on snow and ice, reducing their reflectivity. Soot particles in the air are a contributing factor in respiratory diseases.

Other Word Forms

  • sootless adjective
  • sootlike adjective

Etymology

Origin of soot

before 900; Middle English; Old English sōt; cognate with Old Norse sōt

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Footage of the aftermath shows the entire side of the building blackened with soot with a plume of smoke rising into the air.

From BBC • Mar. 27, 2026

When there is incomplete burning of oil – when there is not enough oxygen - carbon monoxide and soot particles can be released instead of carbon dioxide and water.

From BBC • Mar. 10, 2026

Each day, people inhale millions of microscopic particles, including soot, dust, pollen, microplastics, viruses, and engineered nanoparticles.

From Science Daily • Feb. 8, 2026

For many residents with still-standing homes that were blanketed in toxic soot and ash, clear guidance on how to restore their homes to safe conditions would be a much welcome relief.

From Los Angeles Times • Jan. 28, 2026

When the sweeplight of a harbor patrol ship picked me out of the night like a snowflake on soot, I could not even turn my eyes away from the glare.

From "The Left Hand of Darkness" by Ursula K. Le Guin

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.