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.
On day one, tech billionaires hobnobbed with lawmakers over crab cakes and ribeyes after watching President Donald Trump’s inauguration from the best seats in the house. Riley Beggin, USA TODAY, 25 Jan. 2025 Yes, Doom: The Dark Ages will be available on day one on PC Game Pass and Xbox Game Pass Ultimate. Gordon G. Chang, Newsweek, 24 Jan. 2025 During Trump’s first term, the Senate swiftly confirmed his defense and homeland security secretaries on day one, and President Joe Biden’s choice for director of national intelligence was confirmed on his own Inauguration Day. Lisa Mascaro, Chicago Tribune, 21 Jan. 2025 During Trump’s first term, the Senate swiftly confirmed his Defense and Homeland Security secretaries on day one, and President Biden’s choice for director of national intelligence was confirmed on his own Inauguration Day. Lisa Mascaro, Los Angeles Times, 21 Jan. 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

Dictionary Entries Near day one

Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 31 Jan. 2025.

Last Updated: - Updated example sentences
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