day
DAY
Day (noun) means the 24-hour period during which the Earth completes one rotation, from one midnight to the next. Example: “We spent three days hiking through the mountains.”
noun
1
The 24-hour period during which the Earth completes one rotation, from one midnight to the next.
"We spent three days hiking through the mountains."
"It rained all day on Sunday, so we stayed indoors and played cards."
"Each day she writes a few lines in her notebook before breakfast."
2
The part of the 24-hour period when it is light outside, as opposed to night.
"She prefers to study during the day rather than at night."
"We drove through the day and stopped only when it got dark."
"Owls sleep all day and hunt once the sun has set."
3
The hours spent at work or school.
"He had a long day at the office and just wanted to go home."
"How was your day at school? Did you enjoy the science lesson?"
"After a stressful day, she soaked in a hot bath."
4
A particular period or era, especially referring to someone's lifetime or a past time.
"In her grandmother's day, people wrote letters instead of texting."
"In their day, those singers filled every concert hall in town."
"Back in my grandfather's day, most families grew their own vegetables."
How to use day
Learner’s notesIn plain EnglishOne rotation of the Earth (24 hours), the light part of that period, or — loosely — an era or time in history.
Common pairings
all day
day by day
back in the day
call it a day
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Word forms
- Plural
- days
- Third person singular
- days
- Past tense
- dayed
Fill the gap
Can you complete this real example?
We spent three _____ hiking through the mountains.
Etymology
From Old English dæg, an ancient Germanic word ultimately traced back to a Proto-Indo-European root meaning "to burn" — likely a reference to the heat and light of the sun.
Related words
Rhymes for day
See all rhymes for day →Frequently asked questions
What does “day” mean?
The word “day” means the 24-hour period during which the Earth completes one rotation, from one midnight to the next. In plain terms, one rotation of the Earth (24 hours), the light part of that period, or — loosely — an era or time in history.
How do you pronounce “day”?
“Day” is pronounced DAY (/ˈdeɪ̯/ in IPA).
How do you use “day” in a sentence?
Here is “day” used in a sentence: “We spent three days hiking through the mountains.”
What is another word for “day”?
Words with a similar meaning to “day” include yearday.
What part of speech is “day”?
“Day” is a noun.
Where does the word “day” come from?
The word “day” comes from Old English. From Old English dæg, an ancient Germanic word ultimately traced back to a Proto-Indo-European root meaning "to burn" — likely a reference to the heat and light of the sun.
Is “day” a common word?
“Day” is a very common word in modern English, usually learned at around the A1 level.
How many meanings does “day” have?
“Day” has 4 distinct senses listed in this dictionary. The most common is: the 24-hour period during which the Earth completes one rotation, from one midnight to the next.
What is the difference between a day and daytime?
A day in this sense is the full 24-hour period from one midnight to the next, covering both light and dark. Daytime is only the lit part, from sunrise to sunset. So a winter day is still 24 hours long even when its daytime — the hours of daylight — is short.
Why is a day 24 hours long?
A day is the time the Earth takes to spin once on its axis, and that rotation lasts roughly 24 hours. As the planet turns, each place moves from midnight through morning, noon, and evening back to midnight — one full turn, one full day. We divide that span into 24 equal hours.
What are the different types of day?
The everyday calendar day runs midnight to midnight. Astronomers also use the solar day (noon to noon, the basis of our 24 hours) and the sidereal day (one rotation measured against the stars, about four minutes shorter). 'Day' can also mean just the daylight hours, depending on context.
Example sentences
Real-world examples showing day in context, drawn from published sources. Any opinions expressed are those of the original source and do not reflect the views of FreeDict.com.
The Athletics reinstated slugger Nick Kurtz from the 10-day injured list before their game Saturday night at Minnesota and slotted him into the lineup as the designated hitter, batting second.
From
ESPN · Jul 25, 2026
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