\ ˈfȯg How to pronounce fog (audio) , fäg\

Definition of fog

 (Entry 1 of 2)

1a : 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
3a : 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

Definition of fog (Entry 2 of 2)

transitive verb

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

intransitive verb

1 : to become covered or thick with fog
2a : to become blurred by a covering of fog or mist
b : to become indistinct through exposure to light or radiation

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Other Words from fog


fogless \ ˈfȯg-​ləs How to pronounce fogless (audio) , ˈfäg-​ \ adjective

Synonyms & Antonyms for fog

Synonyms: Noun

Synonyms: Verb

Antonyms: Verb

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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: Noun Rodney Smith recalled turnovers, but Leidner’s was the game’s only one and might have felt like multiple given the magnitude and the fog of time. Andy Greder, Twin Cities, "Gophers’ 2016 loss at Penn State helped Nittany Lions return to prominence," 6 Nov. 2019 Hillsides glowed orange, backyards were stained black and a thick fog of smoke lingered in the air Monday morning in Windsor, hours after the Kincade Fire crept to the edge of town. Megan Cassidy,, "Lessons learned from last big Sonoma blaze: ready to run, ready to fight," 29 Oct. 2019 On Sunday, the Globe’s Jenna Russell told the tale of renowned Harvard Law School Professor Charles J. Ogletree Jr.’s journey into the fog of Alzheimer’s disease., "1. Tell us a bit about how the story come about. Did you approach the Ogletrees?," 29 Oct. 2019 In the fog of war, at least one thing is becoming all too clear: The half-decade-old experiment of an autonomous Syrian Kurdish enclave — backed by American arms and air power — has come to a shuddering halt. Ishaan Tharoor, The Denver Post, "Tharoor: Trump’s lose-lose game in Syria," 15 Oct. 2019 Though that is widely expected to be made up in the third quarter, few economists expect any material change in the outlook as long as the fog of Brexit remains. Pan Pylas, San Diego Union-Tribune, "UK rate-setter hints at cut even if no-deal Brexit avoided," 27 Sep. 2019 In addition to cryptocurrency, researchers have looked to apply zero-knowledge proofs to digital identification mechanisms, a secure alternative to the fog of birth certificate photocopies and smartphone photos of passports. Wired, "Hacker Lexicon: What Are Zero-Knowledge Proofs?," 14 Sep. 2019 Kelly’s book offers many exercises to contact that spacious sense so often obscured by the fog of thought. Ephrat Livni, Quartzy, "Enjoy the liberation of meditation without pain—or contemplation," 6 Sep. 2019 Atwood famously wrote part of The Handmaid’s Tale in Cold War–era Berlin, influenced by the fog of distrust that shrouded the East. Time, "The Handmaid's Tale Was a Warning. Three Decades Later, Margaret Atwood Is Back With Another," 3 Sep. 2019 Recent Examples on the Web: Verb When a worker fogs the streets with pesticide, Ki-taek instructs his family to leave the windows open, in hopes the chemicals will kill the stink bugs inside the place. Bill Goodykoontz, azcentral, "Five stars for compelling new indie film ‘Parasite’," 24 Oct. 2019 That means your hair probably won’t spontaneously curl and your glasses won’t fog. Johnny Diaz,, "Fall has arrived — can you feel it? Here are 5 subtle signs that it’s autumn in South Florida," 23 Sep. 2019 However, the seal separating the two panes can fail on double-pane windows, allowing outside air and moisture to fog up the glass. Stacy Argo, Houston Chronicle, "GHBA Remodelers Council: Consider adding storm windows to your home," 28 July 2019 The streamlined nose bridge can be opened or closed to facilitate airflow and stop fogging. Roy M. Wallack, Los Angeles Times, "At last, sunglasses designed for the sport you love," 13 Sep. 2019 Bob is fogged in by Alzheimer’s and unsteady from Parkinson’s. Andy Newman, New York Times, "On the Job, 24 Hours a Day, 27 Days a Month," 2 Sep. 2019 Just talking about how to write a good one — which words to use and which to avoid — is so steamy, her glasses fog up. Lisa Bonos, Dallas News, "Romance novelist Helen Hoang writes about love on the autism spectrum," 23 July 2019 Just talking about how to write a good one — what words to use and which to avoid — is so steamy, her glasses fog up. Lisa Bonos, Washington Post, "A romance novelist struggled with Asperger’s. Now she writes about love on the spectrum.," 19 July 2019 Dixon's test consisted only of the framework, not the polycarbonate laminated screen that is meant to have an anti-reflective coating on the screen's interior, anti-fogging device and possible tear-offs. Robby General, Indianapolis Star, "Scott Dixon tests IndyCar's Aeroscreen prototype in simulator," 2 July 2019

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

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First Known Use of fog


1544, in the meaning defined at sense 1a


circa 1592, in the meaning defined at transitive sense 1

History and Etymology for fog


probably back-formation from foggy

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Statistics for fog

Last Updated

13 Nov 2019

Time Traveler for fog

The first known use of fog was in 1544

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More Definitions for fog


How to pronounce fog (audio)

English Language Learners Definition of fog

 (Entry 1 of 2)

: many small drops of water floating in the air above the ground, the sea, etc.
: a state of mental confusion



English Language Learners Definition of fog (Entry 2 of 2)

: to cover or fill (something) with small drops of water : to make (something) foggy
: to become foggy
: to make (someone or something) confused


\ ˈfȯg How to pronounce fog (audio) , ˈfäg\

Kids Definition of fog

 (Entry 1 of 2)

1 : tiny drops of water floating in the air at or near the ground
2 : a confused state of mind I woke up in a fog.


fogged; fogging

Kids Definition of fog (Entry 2 of 2)

: to cover or become covered with tiny drops of water Steam from the shower fogged the mirror.
\ ˈfäg, ˈfȯg How to pronounce fog (audio) \
fogged; fogging

Medical Definition of fog

: to blur (a visual field) with lenses that prevent a sharp focus in order to relax accommodation before testing vision

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More from Merriam-Webster on fog

Thesaurus: All synonyms and antonyms for fog

Rhyming Dictionary: Words that rhyme with fog

Spanish Central: Translation of fog

Nglish: Translation of fog for Spanish Speakers

Britannica English: Translation of fog for Arabic Speakers Encyclopedia article about fog

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