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 It’s been fun to watch from day one of her journey from the program. Hunter Bailey, Charlotte Observer, 16 May 2024 Meghan Markle had some empowering words to share during day one of her Prince Harry’s visit to Nigeria. Kirsty Hatcher, Peoplemag, 10 May 2024 See all Example Sentences for day one 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'day one.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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 3 Jun. 2024.

Last Updated: - Updated example sentences
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