grayout

noun

gray·​out ˈgrā-ˌau̇t How to pronounce grayout (audio)
variants or less commonly greyout
plural grayouts also greyouts
: a transient dimming or haziness of vision resulting from temporary impairment of cerebral circulation

Word History

First Known Use

1942, in the meaning defined above

Time Traveler
The first known use of grayout was in 1942

Rhymes for grayout

See All Rhymes for grayout

Browse Nearby Words

gray oak
grayout
gray out
See all Nearby Words

Cite this Entry

“Grayout.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/grayout. Accessed 10 Jun. 2026.

Copy Citation

Medical Definition

grayout

1 of 2 noun
gray·​out
variants or chiefly British greyout
ˈgrā-ˌau̇t How to pronounce grayout (audio)
: a transient dimming or haziness of vision resulting from temporary impairment of cerebral circulation compare blackout, redout

gray out

2 of 2 intransitive verb
ˌgrā-ˈau̇t How to pronounce gray out (audio)
: to experience a grayout compare black out, red out
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of foible

See Definitions and Examples »

Popular in Grammar & Usage

See More

Every Letter Is Silent, Sometimes: A-Z List of Examples

5 Verbal Slip Ups and Language Mistakes

Regarding the Incorrect Use of 'Decimate'

Is that lie 'bald-faced' or 'bold-faced'?

The Difference Between 'i.e.' and 'e.g.'
See More

Popular in Wordplay

See More

What to Call the Inept, Incompetent, and Inferior

Strange Words for Body Functions

Where does 'curiosity killed the cat' come from?

Cattywampus, Taradiddle, and More Funny-Sounding Words

Is “GIF” Pronounced “Jiff” or “Giff”?
See More

Popular

See More

Every Letter Is Silent, Sometimes: A-Z List of Examples

What to Call the Inept, Incompetent, and Inferior

Strange Words for Body Functions
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
a cup of tea and a golf ball on tee side by side
Sounds Like... Quiz June 2026 Choose the word that sounds like it fits the clue...
See All