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.
While sustainability has been a buzzword over the last decade, Krakoff told Fairchild Studio that what is different about John Hardy is that sustainability has been a part of the brand DNA since day one. Fairchild Studio, Footwear News, 6 June 2025 Track these results from day one and get the reps in on repeat. Jodie Cook, Forbes.com, 5 June 2025 One of our testers has been using the vacuum since the end of 2023 and says the suction is just as strong as day one. Toni Sutton, People.com, 4 June 2025 Homes first marketed through MRED’s Private Listing Network sold 55% faster, for more money, and at a higher percentage of list price (97.5% versus 95.4%) than those listed publicly from day one. Mike Golden, Chicago Tribune, 2 June 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 12 Jun. 2025.

Last Updated: - Updated example sentences
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