one day

phrase

1

: at some time in the future

One day, it'll happen. You'll see.

People may one day be able to take vacations to the moon.

2

: on a day in the past

I went to her house one day and had lunch with her.

One day, we had a terrible argument.

Examples of one day in a Sentence

Recent Examples on the Web

Spacecraft could one day change their shape after reaching orbit, allowing operators to add capabilities without launching an entirely new vehicle. — Aamir Khollam, Interesting Engineering, 29 Oct. 2026

At the same time, quantum could one day deliver commercial value in almost every industry, from pharmaceuticals and finance to logistics and energy. — Sam Birchall, Fortune, 29 Oct. 2026

Then one day, while scrolling through Instagram, Alyssa came across a post of Erik and two friends sitting on a Central Park bench. — Alexandra MacOn, Vogue, 29 Oct. 2026

And then, one day, several police cars descend on the house with a warrant to confiscate Philip’s computer and hard drives. — ABC News, 28 Oct. 2026

Rhymes for one day

• aaa
• alleyway
• alumnae
• anime
• anyway
• arete
• attache
• axillae
• baa
• beaujolais
• bouvier
• breakaway