SINCE 1828

An Encyclopædia Britannica Company

one day

Definition of one day

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.

Word by Word Definitions

: the time of light between one night and the next
: daylight
: daytime

See the full definition of day

Seen and Heard

What made you want to look up one day? Please tell us where you read or heard it (including the quote, if possible).

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WORD OF THE DAY

alleviate

play

to relieve or lessen

Words at Play

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We're Down With You Being—or Your Being?—a Square

It's about (you? your?) having your say.

Devilish Words

Don't blame a word use error on the devil.

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How 'Wonderful' Lost Its Sense of Wonder

A case of semantic bleaching

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Don't Let Reading This Be Another 'Coulda' 'Shoulda' 'Woulda'

PSA: They're three separate words.

Ask the Editors

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Words of the Year: 1066

Or, Why Pig Meat is Called 'Pork' and Cow Meat is Called 'Beef'

How Often Is 'Biweekly'?

Don't get us started on 'bimonthly'

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Irregardless

It is in fact a real word (but that doesn't mean you should use it).

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Weird Plurals

One goose, two geese. One moose, two... moose. What's up with that?

Word Games

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Time Traveler Quiz: Which Word Came First?

Which word entered the English language first?

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Name More Food!

Test your knowledge of food vocabulary!

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How Strong Is Your Vocabulary?

How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

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SCRABBLE® Sprint

SCRABBLE® fans, sharpen your skills!

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