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.
In my experience, no CMO truly succeeds without adopting this mindset—much like in politics, where the vice president is prepared to lead on day one. Tifenn Dano Kwan, Forbes, 3 Dec. 2024 Both of these steps had been mandated by UN Security Council Resolution 1701 in 2006—but its terms were never enforced, and Hezbollah violated its terms from day one. Stuart E. Eizenstat, The Atlantic, 2 Dec. 2024 Best Amazon Black Friday Deals on Car Seats and Strollers Ultimately, there are only a few items babies really need from day one. Emily Hochberg, Parents, 29 Nov. 2024 My office has identified several of our properties and is standing by, ready to make this happen on day one of the Trump presidency. Dan Perry, Newsweek, 26 Nov. 2024 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 15 Dec. 2024.

Last Updated: - Updated example sentences
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