\ ˈdā \

Definition of day 

(Entry 1 of 4)

1a : the time of light between one night and the next the shortest day of the year

b : daylight sense 1 woke up at the break of day

c : daytime sleeps during the day and works at night

2 astronomy : the period of rotation of a planet (such as earth) or a moon on its axis the length of one day on Mars

3 : the mean solar day of 24 hours beginning at midnight by mean time open seven days a week the first day of every month Take one pill two times a day.

4 : a specified day or date their wedding day the day of her birth

5 : a specified time or period : age in grandfather's day often used in plural the old daysthe days of sailing ships

6 : the conflict or contention of the day played hard and won the day

7 : the time established by usage or law for work, school, or business starts his day with a cup of coffee after a long day at school We have a busy day tomorrow.

day after day

: for an indefinite or seemingly endless number of days wore the same pants day after day

day in, day out

: for an indefinite number of successive days does the same thing at work day in, day out


biographical name (1)
\ ˈdā \

Definition of Day (Entry 2 of 4)

Clarence Shepard, Jr. 1874–1935 American author


biographical name (2)

Definition of Day (Entry 3 of 4)

Thomas 1748–1789 English author


biographical name (3)

Definition of Day (Entry 4 of 4)

William Rufus 1849–1923 American statesman and jurist

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Synonyms & Antonyms for day

Synonyms: Noun

daylight, daytime

Antonyms: Noun

night, nighttime

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Examples of day in a Sentence


We're open seven days a week, 365 days a year. Payment is due on the first day of every month. “What day of the week is the 28th?” “It's a Friday.” He spent five days in the hospital. She left on Thursday and came back four days later. That was the happiest day of my life. Parenthood gets better every day. The office is closed for the day. She works eight hours a day. It costs 10 dollars a day to park there.
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Recent Examples on the Web: Noun

The general idea: Making a good pass won't necessarily lead to a win that day. Eddie Pells, The Christian Science Monitor, "Bond between players and coach may have saved Thai boy's lives," 13 July 2018 Over several hours that day, her family said, Ms. Daniels gasped for air. New York Times, "‘Totally Preventable’: How a Sick Woman Lost Electricity, and Her Life," 13 July 2018 The Ukrainian woman on the phone that day worried about the U.S. selling Ukraine to the highest bidder. Nina Jankowicz, The New Republic, "Available in Helsinki: the Fate of Eastern Europe," 13 July 2018 The premiere is at 10 p.m. Sunday, but it can be seen earlier that day on streaming, online and On Demand. Hal Boedeker,, "'Jonestown: An American Tragedy,' Sacha Baron Cohen: This weekend," 13 July 2018 In his post-practice news conference Friday, Dixon revealed that he was relieved that his tough day in Iowa didn't cost him much in the championship standings. Jim Ayello, Indianapolis Star, "Scott Dixon climbs back atop IndyCar mountain as Hondas dominate Day 1 in Toronto," 13 July 2018 Police found those two guns inside White’s silver Toyota Corolla, a car witnesses saw speeding from Cash America Pawn that day, Tallahassee police said. Howard Cohen, miamiherald, "A man stole a gun from a store, cops say. But what a manager did next got him fired.," 12 July 2018 Some posit that the silent apparition with the Gibson Girl hair is the spirit of the 55 horses that perished on that terrible day. Maria L. La Ganga, idahostatesman, "What’s behind ’60s-era paneling at El Korah Shrine? A ballroom’s worth of ’20s art.," 12 July 2018 That excitement continued when Gaga posted a few pictures to Instagram later that day, with the people tagged in the pictures sending Little Monsters into a frenzy. Connor Whittum, Billboard, "Lady Gaga Reunites With 'Born This Way' Era Artistic Directors & Photographers," 12 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'day.' 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 day


before the 12th century, in the meaning defined at sense 1a

History and Etymology for day


Middle English, from Old English dæg; akin to Old High German tag day

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Learn More about day

Dictionary Entries near day






day's duty

day's work

Statistics for day

Last Updated

18 Sep 2018

Look-up Popularity

Time Traveler for day

The first known use of day was before the 12th century

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More Definitions for day



English Language Learners Definition of day

: a period of 24 hours beginning at midnight : one of the seven time periods that make up a week

: the time of light between one night and the next : the part of the day when light from the sun can be seen

: the part of the day when people are usually most active and when most businesses are open


\ ˈdā \

Kids Definition of day

1 : the time between sunrise and sunset : daylight

2 : the time a planet or moon takes to make one turn on its axis A day on earth lasts 24 hours.

3 : a period of 24 hours beginning at midnight The offer expires in ten days.

4 : a specified day or date Tuesday is Election Day.

5 : a particular time : age There was no Internet in your grandparent's day.

6 : the time set apart by custom or law for work He works an eight-hour day.

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Comments on day

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


the setting in which something occurs

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