\ ˈfȯg , 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, ˈfäg- \ adjective

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

After a few films full of all-you-can-eat chest-thumping, Reed’s movie is a necessary digestif, all the joys of a Marvel movie shrunk down into a quick caper that cuts through the post-Infinity War fog. Angela Watercutter, WIRED, "Ant-Man and the Wasp and the Importance of Small Stories in Big Universes," 5 July 2018 Through the fog of cigarette smoke and heavy stage lighting, Hardy hoped his hoax would work. Aaron Gilbreath, Longreads, "Forced to Perform As Aretha Franklin," 2 July 2018 Through the fog of cigarette smoke and heavy stage lighting, Hardy hoped his hoax would work. Jeff Maysh, Smithsonian, "The Counterfeit Queen of Soul," 28 June 2018 Last week, however, some marvelous news crept through the fog of anxiety., "Celebrating The 15th Anniversary Of The Trashiest Time In Reality TV History," 11 June 2018 Indeed, depression is something that obliterates the ability to see light through the fog. Christine M. Flowers,, "Kate Spade's tragic suicide should be a reminder to listen to those you love | Christine Flowers," 7 June 2018 Three years after American Pharoah won at Pimlico in a driving rain storm, Mike Smith rode Justify through thick fog that engulfed the racetrack. kansascity, "Justify wins Preakness, has two legs of Triple Crown | The Kansas City Star," 19 May 2018 Flying through fog and rain Lamborn climbed into clouds to pass over Snowshoe Mountain. Eric Tegler, Popular Mechanics, "'A Suicide Club': How WWI Pilots Pioneered the Age of Airmail," 9 May 2018 Increase stopping distance in low-visibility areas and remember to leave the headlights on when driving through fog. Rosemarie Stein,, "Portland Metro Tuesday Traffic: Fog and icy spots for the commute," 6 Mar. 2018

Recent Examples on the Web: Verb

In its place, the raptors come to the kitchen door and snort, fogging up the window as only a warm-blooded animal can do. NBC News, "'Jurassic World': Paleontologist who inspired Alan Grant role talks real-life dino science," 20 June 2018 But his profile is solemn: a sharp jawline, chin raised and jutted, tinted sunglasses that appear more fogged-over than tinted, hair sheared short, perhaps by an electric razor. New York Times, "The Artists Who Brought Asian-Americans Into the Annals of Contemporary Art," 12 Apr. 2018 The Wildcat webcam late Monday afternoon was fogged in, with just a few trees showing in the foreground. Katie Camero,, "Here’s a cool thought: There’s still snow on Mount Washington," 2 July 2018 Instead, Jurassic Park featured the raptors fogging a kitchen window with their breath before opening the kitchen door — something only warm-blooded animals could do. Alessandra Potenza, The Verge, "Were real dinosaurs as bulletproof as the one in Jurassic World: Fallen Kingdom?," 19 June 2018 Read More Worker saw a 'fogged up' car in a parking lot. Kaitlyn Schwers, kansascity, "They left 13 dogs in a hot car for hours, Missouri cops say. Now they face charges," 31 May 2018 The family hiked up and skied above the lift line, the sandwiches in their pockets fogging the cellophane. Naomi Fry, The New Yorker, "Rachel Kushner’s Immersive Fiction," 23 Apr. 2018 After a short time, Mr. Garment said, an officer noticed that Mr. Pritchett was not breathing and the mask had fogged up. Ashley Southall And Nate Schweber, New York Times, "Police Investigate Officers’ Actions in the Death of a Bronx Man in Custody," 29 Jan. 2018 Once again, riders waited a long time in a car fogged with smoke or dust before anyone evacuated them. Fredrick Kunkle, Washington Post, "Metro riders have adjusted after years of subway troubles: They expect the worst," 17 Jan. 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

Phrases Related to fog

fog lamp

fog light

Statistics for fog

Last Updated

18 Sep 2018

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 , 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 \
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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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).


alleviating pain or harshness

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