soot

noun \ ˈsu̇t , ˈsət , ˈsüt \

|Updated on: 10 Aug 2018

Definition of soot

: a black substance formed by combustion or separated from fuel during combustion, rising in fine particles, and adhering to the sides of the chimney or pipe conveying the smoke; especially : the fine powder consisting chiefly of carbon that colors smoke

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Recent Examples of soot from the Web

These epidemiological studies exposed the health dangers of tiny particles of soot less than 2.5 microns in diameter.

— margo oge, Fortune, "Scott Pruitt Is Trying to Pull a Disappearing Act on Science. Here’s How It Would Impact Your Health," 25 June 2018
Burning coal emits soot that even in tiny quantities causes cardiovascular and respiratory illness.

— greg ip, WSJ, "A Costly, Deadly Obsession With Coal," 6 June 2018
Fireworks release nefarious particles such as soot, ash and metals into the atmosphere, and air monitors in the San Joaquin Valley have accordingly detected unsafe spikes in PM concentrations every July 4 evening, the district said.

— jordan cutler-tietjen, sacbee, "Here's the air quality outlook for July 4 and beyond, amid Northern California wildfires," 3 July 2018
That dust is actually a mix of grease, soot and silicate sand.

— jason daley, Smithsonian, "Our Galaxy Is Really Greasy and Smells Like Moth Balls," 28 June 2018
Another decision swept aside a key pillar of Maryland's plan to reduce soot and smog.

— christina tkacik, baltimoresun.com, "Who is Brett Kavanaugh? The Marylander might be Trump's next Supreme Court pick," 28 June 2018
Fun fact: when the chapel was finished, Tiffany was adamant that no gas lamps be allowed inside because the soot would spoil his work.

— aimee levitt, Chicago Reader, "Lincoln, lizard mounds, angels, devil’s curses, and junk food magnates: midwestern cemeteries have ’em all," 30 May 2018
The message to the administration was clear: Forget about your plan to unleash on freeways a class of rebuilt trucks that spew as much as 400 times the choking soot that conventional new big rigs do.

— evan halper, latimes.com, "EPA used disavowed research to justify putting dirtier trucks on the road," 29 May 2018
Scientists who studied the wildfire said that nearly a third of the soot landed on Greenland’s ice sheet.

— megan gannon, Scientific American, "Greenland's Biggest Fire Is a "Warning" for Its Future," 14 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'soot.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.