day one

noun

often capitalized D&O
: the first day or very beginning of something

Examples of day one in a Sentence

We've known this about the project since Day One. since day one of this project, we've always insisted that we would create the best product possible without any consideration of cost
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.
Mason Graham comes in with the ability to play at either defensive tackle spot and the potential to start on day one. Nick Harris, Fort Worth Star-Telegram, 14 Mar. 2025 From day one, Trump has shown little interest in promoting ethical conduct. Abdallah Fayyad, Vox, 14 Mar. 2025 Donald Trump promised Americans a golden age on day one. Jay O'Brien, ABC News, 11 Mar. 2025 Other needs include upgrading the defense corps, acquiring a veteran goalie to potentially pair with Yaroslav Askarov, bringing in another scoring winger, and adding some size and sandpaper to help the Sharks become a more difficult team to play against, which has been Grier’s goal since day one. Curtis Pashelka, The Mercury News, 10 Mar. 2025 See All Example Sentences for day one

Word History

First Known Use

1971, in the meaning defined above

Time Traveler
The first known use of day one was in 1971

Browse Nearby Words

Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 23 Mar. 2025.

Last Updated: - Updated example sentences
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