\ 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

daze, dazedness, haze, muddle, spin, swoon

Synonyms: Verb

becloud, befog, blur, cloud, confuse, muddy, obfuscate

Antonyms: Verb

clarify, clear (up), illuminate

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Examples of fog in a Sentence


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.


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

The Bay Area's mild temperatures, wet winters and dry summers, coupled with San Francisco's famous coastal fog, provide a range of climatic conditions that exist in few other botanical gardens in the world., "Gardener Appreciation Day at the SF Botanical Garden!," 11 Sep. 2019 Most fog from northern and eastern sections of Denver to DIA, then East & Northeast toward Fort Morgan and Limon. Kirk Mitchell, The Denver Post, "Denver weather: Fog could impact commute before sun breaks through," 9 Sep. 2019 The fog will lift after 8 a.m. and today will be mostly sunny with highs near 86 and a slight chance of showers after 2 p.m., according to the weather service. Andrea Perez Balderrama, Detroit Free Press, "Dry and warm weather on tap for metro Detroit today," 19 Aug. 2019 As the fog slowly lifted, the steeply terraced vineyards surrounding the town came into focus, along with a view of the Alps beyond. Lettie Teague, WSJ, "Why Wine Lovers Flock to a Foggy Corner of Italy," 29 Nov. 2018 The fog has lifted, just as the star departs in her mom car. Janet Mock, Marie Claire, "Kerry Washington's Next Act," 8 Oct. 2018 The second year is when emotions aren’t as aggressive, the fog lifts and many people are ready to make life changes. Christen A. Johnson,, "Thinking of setting up a friend who lost a spouse? Here's when to do it," 8 June 2018 Another surprise awaited, once the fog of anesthesia lifted: Scattered across Facebook, Instagram and Twitter were hundreds of posts with the hashtag #moveforjenn. charlotteobserver, "This young mom had a date to get her foot amputated – and 7 long weeks to dread it. | Charlotte Observer," 21 Mar. 2018 The last step was the hair, which fog doesn’t lift or wave around the way water would. Tim Grierson, Popular Mechanics, "The 2018 Incredibly Special Effects Awards," 26 Feb. 2018

Recent Examples on the Web: Verb

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 His breath, hissing out into the moonlit air, would have fogged the lenses. David Canfield,, "First Look: The Andromeda Strain is back with a new look for its 50th anniversary," 26 June 2019 The detective won’t forget the video — a bag over the little girl’s face, her tiny gasps fogging the plastic. Tim Prudente,, "Speaking for baby Rose: How a Baltimore detective found his purpose investigating child abuse," 6 June 2019 The Reflection, Celebrity’s largest ship, even offers a suite with a glass shower cantilevered out over the sea (don't worry about peeping Toms; the glass digitally fogs for privacy). Condé Nast Traveler, "The Best Cruise Lines in the World: 2018 Readers' Choice Awards," 9 Oct. 2018

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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Learn More about fog

Dictionary Entries near fog







fog belt

Statistics for fog

Last Updated

18 Sep 2019

Look-up Popularity

Time Traveler for fog

The first known use of fog was in 1544

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More Definitions for fog



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

Rhyming Dictionary: Words that rhyme with fog

Thesaurus: All synonyms and antonyms for 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

Comments on fog

What made you want to look up fog? Please tell us where you read or heard it (including the quote, if possible).


miscellaneous remnants or debris

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