day one

noun

often capitalized D&O

: the first day or very beginning of something

Synonyms

• alpha
• baseline
• beginning
• birth
• commencement
• dawn
• genesis
• get-go
• git-go
• inception
• incipience
• incipiency
• kickoff
• launch
• morning
• nascence
• nascency
• onset
• outset
• start
• threshold

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

In fact, resilient companies that embrace a forward-looking product development mentality build that very concept into the product from day one, configuring a flexible architecture that can support new modular components and easily adapt to meet demand. —Haresh Bhungalia, Forbes, 3 Oct. 2024

Yeah, well, Kamala Harris’ day one was Donald Trump's failure on COVID that led to the collapse of our economy. —Cheryl V. Jackson, The Indianapolis Star, 2 Oct. 2024

Yeah, well, Kamala Harris' day one was Donald Trump's failure on COVID that led to the collapse of our economy. —Stefan Becket, CBS News, 2 Oct. 2024

From day one, President Biden and Vice President Harris made a foundational choice that in a more competitive and combustible world, the United States cannot go it alone. —Antony J. Blinken, Foreign Affairs, 1 Oct. 2024

Word History

First Known Use

1971, in the meaning defined above