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
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Kennedy says the order to remove the mineral, which the US has been adding to its drinking water for over 70 years to combat tooth decay, will be issued day one. WIRED, 4 Nov. 2024 Imagine walking through your perfect itinerary for your trip to Rome only to have blisters and sore feet on day one, curbing your ability to wander the city’s romantic streets. Kelsey Glennon, Travel + Leisure, 3 Nov. 2024 First of all, Gina and I have always been authentic from day one. Louis Staples, Variety, 1 Nov. 2024 Prodigy used to come to Buffalo and f—k with us on his own since day one. Angel Diaz, Billboard, 1 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 17 Nov. 2024.

Last Updated: - Updated example sentences
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