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
Examples of fog in a Sentence
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
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Recent Examples on the Web
TIME, 19 Dec. 2023
These dudes figured out how to get an airplane out of the sky, 100-feet up, with two living people in it, in the fog and the mist.
—Dan Morse, Washington Post, 17 Dec. 2023
The gore fabric in the ventilation system, which is meant to breathe the same way as a good ski shell, lets moisture out but not in, preventing fog.
—Douglas Schnitzspahn, Travel + Leisure, 13 Dec. 2023
As the apples are ripening, the morning fog often gives way to warm sun.
—Ian James, Los Angeles Times, 29 Nov. 2023
Smoke particles attach to water molecules in the fog, creating a denser haze that lowers visibility to less than ten feet, reports Mike Bedigan for the Independent.
—Margaret Osborne, Smithsonian Magazine, 10 Nov. 2023
Clouds of fog in neon yellow and bright fuchsia gave way to flowing silks and capes that billowed like parachutes in the wind.
—Nicole Phelps, Vogue, 11 Dec. 2023
Breezes calm down a good amount, and that could allow a few patches of fog to develop in the early morning hours.
—A. Camden Walker, Washington Post, 8 Dec. 2023
With winter coming, here in the North, there is no fog of war, apart from half a million mines, according to Nayev.
—Oleksiy Pshemyskiy, ABC News, 25 Nov. 2023
Elizabeth Cooney, STAT, 15 Dec. 2023
Inside Dorian restaurant the windows are fogging up with quiet conversations, candles blink, and a gleaming, rarefied Holland Park evening is coming to life.
—Danielle Pergament, Allure, 14 Dec. 2023
For an enjoyable day on the slopes, choose a pair of goggles that will protect your eyes and won’t fog up.
—Douglas Schnitzspahn, Travel + Leisure, 13 Dec. 2023
Additionally, the nose strip works to prevent fogging if your child wears glasses.
—Dorian Smith-Garcia, Parents, 18 Aug. 2023
Hotels that want to exude a sense of luxurious relaxation have been designing their own candles for decades, and no one who stepped into an Abercrombie & Fitch store in the 2000s will ever forget the olfactory sting of the brand’s musky cologne that fogged their retail stores.
—T.m. Brown, New York Times, 20 Oct. 2023
To see which areas will be fogged, visit the department's website or call the mosquito hotline at 502-574-6641.
—Caleb Wiegandt, The Courier-Journal, 25 July 2023
These upgrades were aimed at alleviating an interior fogging problem in winter driving.
—Frank Markus, Car and Driver, 9 Sep. 2023
His face was still red, his glasses fogged over, his very long legs awkwardly folded under the table.
—Lara Vapnyar, The New Yorker, 4 Sep. 2023
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Noun
May got the idea for Rudolph’s glowing nose from gazing out his office window and thinking about how Santa would be able to navigate through the fog over Lake Michigan.
—TIME, 19 Dec. 2023
These dudes figured out how to get an airplane out of the sky, 100-feet up, with two living people in it, in the fog and the mist.
—Dan Morse, Washington Post, 17 Dec. 2023
The gore fabric in the ventilation system, which is meant to breathe the same way as a good ski shell, lets moisture out but not in, preventing fog.
—Douglas Schnitzspahn, Travel + Leisure, 13 Dec. 2023
As the apples are ripening, the morning fog often gives way to warm sun.
—Ian James, Los Angeles Times, 29 Nov. 2023
Smoke particles attach to water molecules in the fog, creating a denser haze that lowers visibility to less than ten feet, reports Mike Bedigan for the Independent.
—Margaret Osborne, Smithsonian Magazine, 10 Nov. 2023
Clouds of fog in neon yellow and bright fuchsia gave way to flowing silks and capes that billowed like parachutes in the wind.
—Nicole Phelps, Vogue, 11 Dec. 2023
Breezes calm down a good amount, and that could allow a few patches of fog to develop in the early morning hours.
—A. Camden Walker, Washington Post, 8 Dec. 2023
With winter coming, here in the North, there is no fog of war, apart from half a million mines, according to Nayev.
—Oleksiy Pshemyskiy, ABC News, 25 Nov. 2023
Verb
But the drug fogged her thinking, keeping her from driving.
—Elizabeth Cooney, STAT, 15 Dec. 2023
Inside Dorian restaurant the windows are fogging up with quiet conversations, candles blink, and a gleaming, rarefied Holland Park evening is coming to life.
—Danielle Pergament, Allure, 14 Dec. 2023
For an enjoyable day on the slopes, choose a pair of goggles that will protect your eyes and won’t fog up.
—Douglas Schnitzspahn, Travel + Leisure, 13 Dec. 2023
Additionally, the nose strip works to prevent fogging if your child wears glasses.
—Dorian Smith-Garcia, Parents, 18 Aug. 2023
Hotels that want to exude a sense of luxurious relaxation have been designing their own candles for decades, and no one who stepped into an Abercrombie & Fitch store in the 2000s will ever forget the olfactory sting of the brand’s musky cologne that fogged their retail stores.
—T.m. Brown, New York Times, 20 Oct. 2023
To see which areas will be fogged, visit the department's website or call the mosquito hotline at 502-574-6641.
—Caleb Wiegandt, The Courier-Journal, 25 July 2023
These upgrades were aimed at alleviating an interior fogging problem in winter driving.
—Frank Markus, Car and Driver, 9 Sep. 2023
His face was still red, his glasses fogged over, his very long legs awkwardly folded under the table.
—Lara Vapnyar, The New Yorker, 4 Sep. 2023
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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 9 Jan. 2024.
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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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