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fog

¹

[ fog, fawg ]

/ fɒg, fɔg /

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noun

a cloudlike mass or layer of minute water droplets or ice crystals near the surface of the earth, appreciably reducing visibility.Compare ice fog, mist (def. 1), smog (def. 1).

any darkened state of the atmosphere, or the diffused substance that causes it.

a state of mental confusion or unawareness; daze; stupor: The survivors were in a fog for days after the catastrophe.

Photography. a hazy effect on a developed negative or positive, caused by light other than that forming the image, by improper handling during development, or by the use of excessively old film.

Physical Chemistry. a mixture consisting of liquid particles dispersed in a gaseous medium.

verb (used with object), fogged, fog·ging.

to cover or envelop with or as if with fog: The steam in the room fogged his glasses.

to confuse or obscure: The debate did little else but fog the issue.

to bewilder or perplex: to fog the mind.

Photography. to produce fog on (a negative or positive).

verb (used without object), fogged, fog·ging.

to become enveloped or obscured with or as if with fog.

Photography. (of a negative or positive) to become affected by fog.

OTHER WORDS FOR fog

3 haze, muddle; trance.

6 cloud, blur, darken, dim.

7 becloud, befog, confuse, muddy, obscure, obfuscate.

8 daze, befuddle, muddle, mystify.

See synonyms for fog on Thesaurus.com

OPPOSITES FOR fog

3 alertness, clarity.

10 clear.

See antonyms for fog on Thesaurus.com

VIDEO FOR FOG

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QUIZ

CAN YOU ANSWER THESE COMMON GRAMMAR DEBATES?

There are grammar debates that never die; and the ones highlighted in the questions in this quiz are sure to rile everyone up once again. Do you know how to answer the questions that cause some of the greatest grammar debates?

Question 1 of 7

Which sentence is correct?

His boss, whom he admires, is waiting to meet with him about the big project.

His boss, who he admires, is waiting to meet with him about the big project.

TAKE THE QUIZ TO FIND OUT

Origin of fog

¹

First recorded in 1535–45; perhaps by back formation from foggy; see fog²

synonym study for fog

3. See cloud.

OTHER WORDS FROM fog

fogless, adjectiveun·fogged, adjectiveun·fog·ging, adjective

Words nearby fog

foeticide, foetid, foetology, foetor, foetus, fog, Fogarty, fog bank, fogbound, fogbow, fogdog

Other definitions for fog (2 of 2)

fog²

[ fog, fawg ]

/ fɒg, fɔg /

noun U.S. and British Dialect.

a second growth of grass, as after mowing.

long grass left standing in fields during the winter.

Origin of fog

²

First recorded in 1300–50; Middle English fogge, from Scandinavian; compare Norwegian fogg “long, scattered grass on damp ground”; further origin uncertain; see also foggy

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use fog in a sentence

It marks a new beginning, escorts us through our mental fog, and gets us safely into the next phase of our day.
The best quick-brew coffee machines|PopSci Commerce Team|September 10, 2020|Popular-Science
The fog of uncertainty caused by the coronavirus pandemic continues to loom — and now that sense of foreboding unknown is starting to affect the norms of fall marketing.
‘We really don’t know’: How the continued uncertainty is shaking up the usual fall ad marketplace|Kristina Monllos|August 31, 2020|Digiday
This might explain why stepping outside on a bright sunny day helps clear the fog from your head.
Explainer: How our eyes make sense of light|Tina Hesman Saey|July 16, 2020|Science News For Students
There I was high enough up to have fog both above and below me.
Explainer: Rainbows, fogbows and their eerie cousins|Matthew Cappucci|May 1, 2020|Science News For Students

That’s because if you’re near fog, you’re probably inside it.
Explainer: Rainbows, fogbows and their eerie cousins|Matthew Cappucci|May 1, 2020|Science News For Students
The stench of corruption is settling over world soccer like a poisonous fog, and players are paying the price.
Is Soccer Great Lionel Messi Corrupt?|Jack Holmes|December 8, 2014|DAILY BEAST
Dawn was rising on November 24, 1964, and there was a slight fog but otherwise clear visibility.
‘Argo’ in the Congo: The Ghosts of the Stanleyville Hostage Crisis|Nina Strochlic|November 23, 2014|DAILY BEAST
A fog of conspiracy—of logic against logic, as Orwell put it—has descended on every major event in the war.
Digital Doublethink: Playing Truth or Dare with Putin, Assad and ISIS|Christopher Dickey, Anna Nemtsova|November 16, 2014|DAILY BEAST
Although some groups, through the thick fog of tear gas, pepper spray and smoke that hung over the city, still lingered.
Frat Culture Clashes With Riot Police at Keene, N.H., Pumpkin Festival|Melanie Plenda|October 19, 2014|DAILY BEAST
So we changed that into a fog machine blast right before I go on.
Oscars Host Neil Patrick Harris on His Best and Worst Emcee Moments (VIDEO)|Neil Patrick Harris|October 15, 2014|DAILY BEAST
The fire along the three miles front is like the rumble of an express train running over fog signals.
Gallipoli Diary, Volume I|Ian Hamilton
The huge sail thrust its yard high above the fog bank, and watchers on the river side saw it.
The Red Year|Louis Tracy
On the 7th of August we neared the Canary Isles, but unfortunately, on account of the thick fog, we could not see them.
A Woman's Journey Round the World|Ida Pfeiffer
If there be no facilities for stopping for the night, a driver is not negligent should he proceed through the fog.
Putnam's Handy Law Book for the Layman|Albert Sidney Bolles
The sand hung in fog-like clouds shrouding the sun, dimming the usual brilliance.
The Wave|Algernon Blackwood

British Dictionary definitions for fog (1 of 2)

fog¹

/ (fɒɡ) /

noun

a mass of droplets of condensed water vapour suspended in the air, often greatly reducing visibility, corresponding to a cloud but at a lower level

a cloud of any substance in the atmosphere reducing visibility

a state of mental uncertainty or obscurity

photog a blurred or discoloured area on a developed negative, print, or transparency caused by the action of extraneous light, incorrect development, etc

a colloid or suspension consisting of liquid particles dispersed in a gas

verb fogs, fogging or fogged

to envelop or become enveloped with or as if with fog

to confuse or become confusedto fog an issue

photog to produce fog on (a negative, print, or transparency) or (of a negative, print, or transparency) to be affected by fog

Word Origin for fog

C16: perhaps back formation from foggy damp, boggy, from fog ²

British Dictionary definitions for fog (2 of 2)

fog²

/ (fɒɡ) /

noun

a second growth of grass after the first mowing
grass left to grow long in winter

Word Origin for fog

C14: probably of Scandinavian origin; compare Norwegian fogg rank grass

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for fog

fog

[ fôg ]

A dense layer of cloud lying close to the surface of the ground or water and reducing visibility to less than 1 km (0.62 mi). Fog occurs when the air temperature becomes identical, or nearly identical, to the dew point.

An opaque or semiopaque condensation of a substance floating in a region or forming on a surface.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Other Idioms and Phrases with fog

fog

see in a fog.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.