plural days
1
a
: 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 days
the 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.

see also day after day, day in and day out

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.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Some companies, like those in Japan, offer incentives like extra vacation days to encourage healthy habits. Basel Ramlawi, Forbes, 17 Dec. 2024 Bessette-Kennedy’s gown also inspired one of Meghan Markle’s wedding day looks: specifically her halter neck Stella McCartney reception dress. Hannah Malach, WWD, 17 Dec. 2024 While three days might not be enough to unlock the mysteries of the cosmos, even a short retreat can offer a profound reconnection with nature and oneself. Julia Eskins, Vogue, 17 Dec. 2024 The acting director was testifying on Thursday about the steps the agency has taken since then to correct some of the issues identified in the various subsequent reviews of that day. Eileen Sullivan, New York Times, 6 Dec. 2024 See all Example Sentences for day 

Word History

Etymology

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

First Known Use

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

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

Dictionary Entries Near day

Cite this Entry

“Day.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day. Accessed 21 Dec. 2024.

Kids Definition

day

noun
1
a
: the time of light between one night and the next
b
2
a
: the time the earth takes to make one turn on its axis
b
: the time required for a heavenly body to turn once on its axis
a lunar day
3
: a period of 24 hours beginning at midnight
4
: a specified day or date
the day of the picnic
their wedding day
5
: a specified time or period : age
in grandmother's day
6
: the conflict or dispute of the day
fought hard and won the day
7
: the time set apart by custom or law for work
the eight-hour day

Biographical Definition

Day 1 of 3

biographical name (1)

Clarence Shepard, Jr. 1874–1935 American author

Day

2 of 3

biographical name (2)

Thomas 1748–1789 English author

Day

3 of 3

biographical name (3)

William Rufus 1849–1923 American statesman and jurist

More from Merriam-Webster on day

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