one day
idiom
1
: at some time in the future
One day, it'll happen. You'll see.
People may one day be able to take vacations to the moon.
2
: on a day in the past
I went to her house one day and had lunch with her.
One day, we had a terrible argument.
Examples of one day in a Sentence
Recent Examples on the Web
Phoenix police officers were involved in a second shooting in just one day, this time near 16th Street and Buckeye Road, spokesperson Sgt.
—
Julie Mendes, AZCentral.com, 3 Oct. 2025
Yom Kippur is the one day when even people who are not particularly observant feel compelled to attend synagogue and refrain from using technology.
—Ivana Kottasová, CNN Money, 2 Oct. 2025
In theory, those savings on manufacturing and fuel could one day result in ever so slightly lower ticket prices for travellers looking to indulge in a private jet experience.
—Mack Degeurin, Popular Science, 2 Oct. 2025
Then one day, the ventilation system started acting funny.
—Charlotte Observer, 2 Oct. 2025
See All Example Sentences for one day
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.
Julie Mendes, AZCentral.com, 3 Oct. 2025
Yom Kippur is the one day when even people who are not particularly observant feel compelled to attend synagogue and refrain from using technology.
—Ivana Kottasová, CNN Money, 2 Oct. 2025
In theory, those savings on manufacturing and fuel could one day result in ever so slightly lower ticket prices for travellers looking to indulge in a private jet experience.
—Mack Degeurin, Popular Science, 2 Oct. 2025
Then one day, the ventilation system started acting funny.
—Charlotte Observer, 2 Oct. 2025
See All Example Sentences for one day
Cite this Entry
“One day.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/one%20day. Accessed 8 Oct. 2025.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
Share