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
Italian Premier Giorgia Meloni and Austrian Chancellor Christian Stocker were on hand for the ceremonial breakthrough of the final meter of rock to open the first tunnel beneath the Brenner Pass, a key junction in an EU rail project that will one day run from Helsinki to Palermo.
—
Dave Smith, Fortune, 19 Sep. 2025
These sensors may one day enable technologies such as GPS-free navigation and autonomous driving that operate with pinpoint accuracy.
—Neetika Walter, Interesting Engineering, 19 Sep. 2025
Safeguarding Legacy And Preventing Dependence Protecting a family’s wealth means thinking not only about children but also about those who may one day marry into the family.
—Monish Verma, Forbes.com, 18 Sep. 2025
Maybe, one day, someone will find out.
—Leah Hudson, Popular Science, 18 Sep. 2025
See All Example Sentences for one day
Examples are automatically compiled from online sources to
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Dave Smith, Fortune, 19 Sep. 2025
These sensors may one day enable technologies such as GPS-free navigation and autonomous driving that operate with pinpoint accuracy.
—Neetika Walter, Interesting Engineering, 19 Sep. 2025
Safeguarding Legacy And Preventing Dependence Protecting a family’s wealth means thinking not only about children but also about those who may one day marry into the family.
—Monish Verma, Forbes.com, 18 Sep. 2025
Maybe, one day, someone will find out.
—Leah Hudson, Popular Science, 18 Sep. 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 20 Sep. 2025.
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