day one

noun

variants often Day One
Synonyms of day onenext
: 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.
Day One offers advocacy support as well as clinical and therapy services to support survivors, victims and their families, according to its website. Katie Mulvaney, The Providence Journal, 3 July 2026 This World Cup has been bringing the absolute goods from day one. Alejandro Avila Outkick, FOXNews.com, 2 July 2026 Every purchase also includes a strap, lock, air pump, and rearview mirrors, giving riders a complete package that's ready for the road from day one. New Atlas, 2 July 2026 The siblings have been there for one another since day one—and Austin’s even been instrumental in masterminding some of his sister’s biggest moments. Bailey Bujnosek, InStyle, 2 July 2026 See All Example Sentences for day one

Word History

First Known Use

1953, in the meaning defined above

Time Traveler
The first known use of day one was in 1953

Browse Nearby Words

Cite this Entry

“Day one.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/day%20one. Accessed 7 Jul. 2026.

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