Other forms: days

A day is a 24-hour period, or the length of time it takes the Earth to rotate fully on its axis. There are 365 days in a year, and 31 days in the month of January.

Most work weeks last five days, and an ordinary weekend gives you two days of freedom before you go back to work or school. Day can also mean the opposite of night, or the time when the sun is up and you're awake. If your grandpa starts his stories with, "Back in my day..." he means an era or a period of time in the past. The Old English root, dæg, means both "day" and "lifetime."

Definitions of day
  1. noun
    time for Earth to make a complete rotation on its axis
    “two days later they left”
    “they put on two performances every day
    “there are 30,000 passengers per day
    synonyms: 24-hour interval, mean solar day, solar day, twenty-four hour period, twenty-four hours
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    the day after today
    the day that includes the present moment (as opposed to yesterday or tomorrow)
    the day immediately before today
    the next day
    the day before
    date, day of the month
    the specified day of the month
    a particular day specified as the time something happens
    due date, maturity, maturity date
    the date on which an obligation must be repaid
    future date
    a particular day in the future that is specified as the time something will happen
    rain date
    an alternative date set for some outdoor event in case it rains on the appointed date
    sell-by date
    a date stamped on perishable produce indicating the date by which it should be sold
    birthday, natal day
    the date on which a person was born
    type of:
    time unit, unit of time
    a unit for measuring time periods
  2. noun
    the period of time taken by a particular planet (e.g. Mars) to make a complete rotation on its axis
    “how long is a day on Jupiter?”
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    lunar day
    the period of time taken for the moon to make one full rotation on its axis (about 27.3 sidereal days)
    type of:
    period, period of time, time period
    an amount of time
  3. noun
    the time for one complete rotation of the earth relative to a particular star, about 4 minutes shorter than a mean solar day
    synonyms: sidereal day
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    type of:
    time unit, unit of time
    a unit for measuring time periods
    sidereal time
    measured by the diurnal motion of stars
  4. noun
    the time after sunrise and before sunset while it is light outside
    “the dawn turned night into day
    synonyms: daylight, daytime
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    dark, night, nighttime
    the time after sunset and before sunrise while it is dark outside
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    the part of the day between noon and evening
    the middle part of the afternoon
    eve, even, evening, eventide
    the latter part of the day (the period of decreasing daylight from late afternoon until nightfall)
    guest night
    an evening when members of a club or college can bring their friends as guests
    type of:
    period, period of time, time period
    an amount of time
  5. noun
    the recurring hours when you are not sleeping (especially those when you are working)
    “my day began early this morning”
    “it was a busy day on the stock exchange”
    “she called it a day and went to bed”
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    workday, working day
    the amount of time that a worker must work for an agreed daily wage
    type of:
    work time
    a time period when you are required to work
  6. noun
    some point or period in time
    “it should arrive any day now”
    “after that day she never trusted him again”
    “those were the days
    “these days it is not unusual”
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    Day of Judgement, Day of Judgment, Doomsday, Judgement Day, Judgment Day, Last Day, Last Judgement, Last Judgment, crack of doom, day of reckoning, doomsday, end of the world, eschaton
    (New Testament) day at the end of time following Armageddon when God will decree the fates of all individual humans according to the good and evil of their earthly lives
    a day when things go poorly
    type of:
    an indefinite period (usually marked by specific attributes or activities)
  7. noun
    a day assigned to a particular purpose or observance
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    Admission Day
    in some states of the United States: a legal holiday commemorating the day the state was admitted to the Union
    Arbor Day
    a day designated for planting trees
    Cinco de Mayo
    the fifth of May which is observed in Mexico and Mexican-American communities in the United States to commemorate the Mexican victory over the French in the Battle of Puebla in 1862
    commencement day, degree day
    the day on which university degrees are conferred
    November 5
    anniversary of the discovery of the Gunpowder Plot
    Inauguration Day, January 20
    the day designated for inauguration of the United States President
    February 29, bissextile day, leap day
    the name of the day that is added during a leap year
    V-day, Victory Day
    the day of a victory
    rag day
    a day on which university students hold a rag
    red-letter day
    a memorably happy or noteworthy day (from the custom of marking holy days in red on church calendars)
    the day on which you receive pay for your work
    election day, polling day
    the day appointed for an election; in the United States it is the 1st Tuesday after the 1st Monday in November
    field day
    a day for outdoor athletic competition
    field day
    (military) a day for military exercises and display
    in the Roman calendar: the 15th of March or May or July or October or the 13th of any other month
    market day
    a fixed day for holding a public market
    Walpurgis Night
    eve of May Day
    December 31, New Year's Eve
    the last day of the year
    January 19, Lee's Birthday, Robert E Lee Day, Robert E Lee's Birthday
    celebrated in southern United States
    the New Year in Vietnam; observed for three days after the first full moon after January 20th
    a day on which work is suspended by law or custom
    February 2, Groundhog Day
    if the ground hog emerges and sees his shadow on this day, there will be 6 more weeks of winter
    February 12, Lincoln's Birthday
    the day on which President Abraham Lincoln is remembered
    February 14, Saint Valentine's Day, St Valentine's Day, Valentine Day, Valentine's Day
    a day for the exchange of tokens of affection
    February 22, Washington's Birthday
    the day on which George Washington is remembered
    March 2, Texas Independence Day
    Texans celebrate the anniversary of Texas' declaration of independence from Mexico in 1836
    March 17, Saint Patrick's Day, St Patrick's Day
    a day observed by the Irish to commemorate the patron saint of Ireland
    All Fools' day, April Fools', April Fools' day
    the first day of April which is celebrated by playing practical jokes
    April 14, Pan American Day
    a day celebrating political and economic unity among American countries
    Patriot's Day
    the 3rd Monday in April; Massachusetts and Maine celebrate the battle of Lexington and Concord in 1775
    First of May, May 1, May Day
    observed in many countries to celebrate the coming of spring; observed in Russia and related countries in honor of labor
    Mother's Day
    second Sunday in May
    Armed Forces Day
    the 3rd Saturday in May
    Davis' Birthday, Jefferson Davis' Birthday, June 3
    celebrated in southern United States
    Flag Day, June 14
    commemorating the adoption of the United States flag in 1777
    Father's Day
    US: third Sunday in June
    Citizenship Day, September 17
    celebrated in the United States
    American Indian Day
    US: the 4th Friday in September
    October 24, United Nations Day
    a day for celebrating the founding of the United Nations
    Allhallows Eve, Hallowe'en, Halloween
    the evening before All Saints' Day; often devoted to pranks played by young people
    saint's day
    a day commemorating a saint
    June 23, Midsummer Eve, Midsummer Night, St John's Eve, St John's Night
    the night before Midsummer Day
    school day
    any day on which school is in session
    speech day
    an annual day in the schools when speeches are made and prizes are distributed
    washday, washing day
    a day set aside for doing household laundry
    wedding day
    the day of a wedding
    anniversary, day of remembrance
    the date on which an event occurred in some previous year (or the celebration of it)
    a day on which half is free from work or duty
    Guy Fawkes Day
    day for the celebration of the discovery of the Gunpowder Plot
    Bonfire Night, Guy Fawkes Night
    effigies of Guy Fawkes are burned on this night
    feast day, fete day
    a day designated for feasting
    New Year's Eve in Scotland
    holy day, religious holiday
    a day specified for religious observance
    Christmas Eve, Dec 24
    the day before Christmas
    legal holiday, national holiday, public holiday
    authorized by law and limiting work or official business
    Poppy Day, Remembrance Day, Remembrance Sunday
    the Sunday nearest to November 11 when those who died in World War I and World War II are commemorated
    Hindu lunar holiday (on the 9th day of Caitra) to celebrate the birth of Rama
    Hindu solar holiday at the beginning of the new astrological year when the sun enters the constellation Aries
    name day
    the feast day of a saint whose name one bears
    an anniversary of the day on which a person was born (or the celebration of it)
    a special anniversary (or the celebration of it)
    wedding anniversary
    the anniversary of the day on which you were married (or the celebration of it)
    semicentenary, semicentennial
    the 50th anniversary (or the celebration of it)
    centenary, centennial
    the 100th anniversary (or the celebration of it)
    the 150th anniversary (or the celebration of it)
    bicentenary, bicentennial
    the 200th anniversary (or the celebration of it)
    tercentenary, tercentennial, triennial
    the 300th anniversary (or the celebration of it)
    quatercentenary, quatercentennial
    the 400th anniversary (or the celebration of it)
    quincentenary, quincentennial
    the 500th anniversary (or the celebration of it)
    millenary, millennium
    the 1000th anniversary (or the celebration of it)
    bimillenary, bimillennium
    the 2000th anniversary (or the celebration of it)
    type of:
    calendar day, civil day
    a day reckoned from midnight to midnight
  8. noun
    an era of existence or influence
    “in the day of the dinosaurs”
    “in the days of the Roman Empire”
    “in the days of sailing ships”
    “he was a successful pianist in his day
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    type of:
    epoch, era
    a period marked by distinctive character or reckoned from a fixed point or event
  9. noun
    a period of opportunity
    “he deserves his day in court”
    “every dog has his day
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    type of:
    chance, opportunity
    a possibility due to a favorable combination of circumstances




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DISCLAIMER: These example sentences appear in various news sources and books to reflect the usage of the word ‘day'. Views expressed in the examples do not represent the opinion of or its editors. Send us feedback
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