1
a
: vapor condensed to fine particles of water suspended in the lower atmosphere that differs from cloud only in being near the ground
b
: a fine spray or a foam for firefighting
2
: a murky condition of the atmosphere or a substance causing it
3
a
: a state of confusion or bewilderment
spent the morning in a fog
b
: something that confuses or obscures
hid behind a fog of rhetoric
4
: cloudiness or partial opacity in a developed photographic image caused by chemical action or stray radiation
fogged; fogging
1
: to cover, envelop, or suffuse with or as if with fog
fog the barns with pesticide
2
: to make obscure or confusing
accusations which fogged the real issues
3
: to make confused
4
: to produce fog on (something, such as a photographic film) during development
1
: to become covered or thick with fog
2
a
: to become blurred by a covering of fog or mist
b
: to become indistinct through exposure to light or radiation
Synonyms
Example Sentences
Noun
Heavy fog made it difficult to see the road.
a climate marked by heavy fogs
The fog reduced visibility to a quarter of a mile.
This problem has me in a fog.
Verb
The steam from the pot was fogging the window near the stove.
The bathroom was all fogged up after my shower.
politicians who try to fog the issue instead of taking a stand
See More
Recent Examples on the Web
Anthony Edwards, San Francisco Chronicle, 15 May 2023
In some communities where water must be trucked in, simple contraptions of plastic or steel mesh called fog catchers have enabled agricultural and reforestation projects.
—Maggie Shipstead Anthony Cotsifas, New York Times, 10 May 2023
Early patchy fog should burn off by midmorning and reveal in-and-out sunshine.
—A. Camden Walker, Washington Post, 7 May 2023
On Tuesday, forecasts called for patchy fog with looming clouds and a chance for isolated showers or thunderstorms west of Del Rio, while Wednesday could see better rain chances along the Rio Grande not but in San Antonio.
—Shepard Price, San Antonio Express-News, 2 May 2023
Though not as common, riders across the country have also left behind more unique possessions like a Danny DeVito Christmas ornament, an ankle monitor, a lightsaber, a Tamagotchi, a fog machine, and even a real-life pet dog and a pair of turtles.
—Alison Fox, Travel + Leisure, 27 Apr. 2023
Although the primary image of the Evergreen State is the rain and fog of Seattle and Puget Sound, the vast majority of wine made here is from the arid region east of the Cascade Mountains.
—Mike Desimone And Jeff Jenssen, Robb Report, 21 Apr. 2023
Search-and-rescue efforts soon transformed into a search-and-recovery mission, though one hampered by thick fog that rendered helicopters useless.
—Alex Riggins, San Diego Union-Tribune, 13 Mar. 2023
Dense fog also set in along the highway near Eklutna Friday, which added to the dangerous driving conditions, the National Weather Service said.
—Tess Williams, Anchorage Daily News, 25 Feb. 2023
Beth Mole, Ars Technica, 27 Apr. 2023
Bhamla and Challita say that similar methods of superpropulsion could one day help wearable devices such as smartwatches remove moisture or prevent droplets from fogging up glasses.
—Jack Tamisiea, Scientific American, 28 Feb. 2023
The shield appeared to fog up at times.
—Calvin Watkins, Dallas News, 11 Sep. 2020
Inglewood’s Friday night Southern Section Division 2 semifinal against West Hills Chaminade went so late that even the smallest breath turned to fog in the dead-of-night cold at South Torrance High, the Sentinels and Eagles trading back-and-forth blows in an instant playoff overtime classic.
—Luca Evans, Los Angeles Times, 18 Nov. 2022
When it is not being used to fog up rock concerts, it’s often used to keep perishables cool during shipping.
—Jennifer Leman, Popular Mechanics, 15 Feb. 2022
Dressed in all black, the Spy Kids alum portrays Trainor's chauffeur, as well as a fan whose glasses fog up just at the sight of the pop star.
—Robin Raven, Peoplemag, 30 Jan. 2023
That snow can pile up and clog your vents, causing your goggles to fog.
—Leslie Hsu Oh, Travel + Leisure, 30 Jan. 2023
Additionally, the fans don’t cool as expected; people overheat and faceplates fog.
—Kate Greene, Discover Magazine, 7 June 2013
See More
Noun
Berkeley and Oakland could have patchy fog Tuesday morning.
—Anthony Edwards, San Francisco Chronicle, 15 May 2023
In some communities where water must be trucked in, simple contraptions of plastic or steel mesh called fog catchers have enabled agricultural and reforestation projects.
—Maggie Shipstead Anthony Cotsifas, New York Times, 10 May 2023
Early patchy fog should burn off by midmorning and reveal in-and-out sunshine.
—A. Camden Walker, Washington Post, 7 May 2023
On Tuesday, forecasts called for patchy fog with looming clouds and a chance for isolated showers or thunderstorms west of Del Rio, while Wednesday could see better rain chances along the Rio Grande not but in San Antonio.
—Shepard Price, San Antonio Express-News, 2 May 2023
Though not as common, riders across the country have also left behind more unique possessions like a Danny DeVito Christmas ornament, an ankle monitor, a lightsaber, a Tamagotchi, a fog machine, and even a real-life pet dog and a pair of turtles.
—Alison Fox, Travel + Leisure, 27 Apr. 2023
Although the primary image of the Evergreen State is the rain and fog of Seattle and Puget Sound, the vast majority of wine made here is from the arid region east of the Cascade Mountains.
—Mike Desimone And Jeff Jenssen, Robb Report, 21 Apr. 2023
Search-and-rescue efforts soon transformed into a search-and-recovery mission, though one hampered by thick fog that rendered helicopters useless.
—Alex Riggins, San Diego Union-Tribune, 13 Mar. 2023
Dense fog also set in along the highway near Eklutna Friday, which added to the dangerous driving conditions, the National Weather Service said.
—Tess Williams, Anchorage Daily News, 25 Feb. 2023
Verb
Enlarge / Eddie Robles drives a Maricopa County Vector Control fogging truck through a neighborhood August 4, 2004, in Tempe, Arizona.
—Beth Mole, Ars Technica, 27 Apr. 2023
Bhamla and Challita say that similar methods of superpropulsion could one day help wearable devices such as smartwatches remove moisture or prevent droplets from fogging up glasses.
—Jack Tamisiea, Scientific American, 28 Feb. 2023
The shield appeared to fog up at times.
—Calvin Watkins, Dallas News, 11 Sep. 2020
Inglewood’s Friday night Southern Section Division 2 semifinal against West Hills Chaminade went so late that even the smallest breath turned to fog in the dead-of-night cold at South Torrance High, the Sentinels and Eagles trading back-and-forth blows in an instant playoff overtime classic.
—Luca Evans, Los Angeles Times, 18 Nov. 2022
When it is not being used to fog up rock concerts, it’s often used to keep perishables cool during shipping.
—Jennifer Leman, Popular Mechanics, 15 Feb. 2022
Dressed in all black, the Spy Kids alum portrays Trainor's chauffeur, as well as a fan whose glasses fog up just at the sight of the pop star.
—Robin Raven, Peoplemag, 30 Jan. 2023
That snow can pile up and clog your vents, causing your goggles to fog.
—Leslie Hsu Oh, Travel + Leisure, 30 Jan. 2023
Additionally, the fans don’t cool as expected; people overheat and faceplates fog.
—Kate Greene, Discover Magazine, 7 June 2013
See More
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'fog.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Word History
Etymology
Noun
probably back-formation from foggy
First Known Use
Noun
1544, in the meaning defined at sense 1a
Verb
circa 1592, in the meaning defined at transitive sense 1
Phrases Containing fog
Dictionary Entries Near fog
Cite this Entry
“Fog.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fog. Accessed 3 Jun. 2023.
Copy Citation
Kids Definition
fog
1 of 2 noun
ˈfȯg 
ˈfäg
1
a
: fine particles of water floating in the atmosphere near the ground
b
: a fine spray or a foam for firefighting
2
: a gloomy condition of the atmosphere or a substance causing it
3
: a state of mental confusion
spent the morning in a fog
fog
2 of 2 verb
fogged; fogging
1
: to cover or become covered with or as if with fog
2
: to make confused
Medical Definition
fog
transitive verb
fogged; fogging
: to blur (a visual field) with lenses that prevent a sharp focus in order to relax accommodation before testing vision
More from Merriam-Webster on fog
Nglish: Translation of fog for Spanish Speakers
Britannica English: Translation of fog for Arabic Speakers
Britannica.com: Encyclopedia article about fog
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