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
The idea that humans could one day populate and even colonize Mars is one no longer confined to the realm of science fiction.
—
Eric Lagatta, USA Today, 22 Aug. 2025
The largest, a 4.0 magnitude earthquake, hit one day ago, while the other, measuring 3.6, was detected on August 14.
—Ca Earthquake Bot, Sacbee.com, 21 Aug. 2025
FanDuel’s announcement came one day after Robinhood launched pro and college football prediction markets within the online broker’s app.
—Ty Roush, Forbes.com, 21 Aug. 2025
The announcement came just one day after Zelenskyy and several European leaders gathered at the White House to debrief following Trump's high-stakes summit with Putin in Alaska.
—Jackson Thompson, FOXNews.com, 20 Aug. 2025
See All Example Sentences for one day
Examples are automatically compiled from online sources to
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Eric Lagatta, USA Today, 22 Aug. 2025
The largest, a 4.0 magnitude earthquake, hit one day ago, while the other, measuring 3.6, was detected on August 14.
—Ca Earthquake Bot, Sacbee.com, 21 Aug. 2025
FanDuel’s announcement came one day after Robinhood launched pro and college football prediction markets within the online broker’s app.
—Ty Roush, Forbes.com, 21 Aug. 2025
The announcement came just one day after Zelenskyy and several European leaders gathered at the White House to debrief following Trump's high-stakes summit with Putin in Alaska.
—Jackson Thompson, FOXNews.com, 20 Aug. 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 25 Aug. 2025.
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