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\ ˈwən 
\
\Definition of one
(Entry 1 of 4)
1 : being a single unit or thing
one day at a time She is one year old.
2a : being one in particular
early one morning The Grand Canyon is one place I'd like to visit.
b : being preeminently what is indicated
one fine person She is one tough teacher.
3a : being the same in kind or quality
both of one species "Puma" and "cougar" are different names for one animal.
b(1) : constituting a unified entity of two or more components
The combined elements form one substance.
(2) : being in agreement or union
am one with you on this
4a : some sense 1 will see you again one day
b : being a certain individual specified by name
one John Doe made a speech
5 : only sense 2a the one person she wanted to marry
one
nounDefinition of one (Entry 2 of 4)
1 : the first whole number above zero — see Table of Numbers
2 : the number denoting unity
3a : the first in a set or series
—often used with an attributive nounday one
b : an article of clothing of a size designated one wears a one
4 : a single person or thing
has the one but needs the other
5 : a one-dollar bill
at one for one
: at harmony : in a state of agreement
: as one example
I for one disagree
one
pronounDefinition of one (Entry 3 of 4)
1 : a certain indefinitely indicated person or thing
saw one of his friends
2a : an individual of a vaguely indicated group : anyone at all
one never knows
b —used as a third person substitute for a first person pronounI'd like to read more but one doesn't have the time.
3 : a single instance of a specified action
felt like belting him one— John Casey
-one
noun suffixDefinition of -one (Entry 4 of 4)
: ketone or related or analogous compound or class of compounds
lactone quinone
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Examples of one in a Sentence
Adjective
There is one minute left in the game.
I have a few one-dollar bills in my purse.
She is one year old. Noun one, two, three, four, …
I don't have any ones. Can you break a five?
I'll be there at one. Pronoun
“I'll have an iced tea, please.” “I'll have one, too.”
Their dog died, but they plan to get another one.
“You should wear the blue one.” “The one with the stripes?” “No, the other one.”
I'd like to see the ring next to that one.
Which one did you like better?
He is the one who called the police.
That's one possible answer—but not the only one.
I would like to read more, but one doesn't have the time.
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Recent Examples on the Web: Adjective Drinkwater didn't make one appearance in a Chelsea shirt last season, whilst Bakayoko spent the season in Italy on loan at AC Milan.
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SI.com, "Chelsea Set to Entertain Offers for Out of Favour Midfield Pair Ahead of Transfer Deadline," 3 Aug. 2019 Decisions made by engineers today, in other words, will determine not how one car drives but how all cars drive.
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Johannes Himmelreich, BostonGlobe.com, "The everyday moral challenges of self-driving cars," 30 Mar. 2018 Decisions made by engineers today, in other words, will determine not how one car drives but how all cars drive.
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Johannes Himmelreich, Smithsonian, "The Ethical Challenges Self-Driving Cars Will Face Every Day," 27 Mar. 2018 Drinkwater didn't make one appearance in a Chelsea shirt last season, whilst Bakayoko spent the season in Italy on loan at AC Milan.
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SI.com, "Chelsea Set to Entertain Offers for Out of Favour Midfield Pair Ahead of Transfer Deadline," 3 Aug. 2019 Decisions made by engineers today, in other words, will determine not how one car drives but how all cars drive.
—
Johannes Himmelreich, BostonGlobe.com, "The everyday moral challenges of self-driving cars," 30 Mar. 2018 Decisions made by engineers today, in other words, will determine not how one car drives but how all cars drive.
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Johannes Himmelreich, BostonGlobe.com, "The everyday moral challenges of self-driving cars," 30 Mar. 2018 Decisions made by engineers today, in other words, will determine not how one car drives but how all cars drive.
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Johannes Himmelreich, BostonGlobe.com, "The everyday moral challenges of self-driving cars," 30 Mar. 2018 Decisions made by engineers today, in other words, will determine not how one car drives but how all cars drive.
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Johannes Himmelreich, BostonGlobe.com, "The everyday moral challenges of self-driving cars," 30 Mar. 2018 Recent Examples on the Web: Noun This weekend’s simulation is something that happens every year, an Operational Readiness Exercise, this one involving a hazmat drill.
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Barrett Swanson, Harper's Magazine, "This Is Not a Test," 23 June 2020 Last year's sale also blacked out Labor Day weekend travel, but this one does not.
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Dawn Gilbertson, USA TODAY, "Ready to fly again? Southwest launches annual fall fare sale, with one-way tickets starting at $39," 23 June 2020 There seems to be consensus on this one among our scientists.
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Cnn Staff, CNN, "The US Wasn't Prepared for Covid-19: Dr. Sanjay Gupta's coronavirus podcast for June 22," 22 June 2020 As always, there’s plenty of room for surprises, but in the meantime, here’s what to expect: iOS 14 There’s bound to be some twists in the details, but broadly speaking this one is pretty much a given.
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Boone Ashworth, Wired, "How to Watch Apple's WWDC 2020 Keynote (and What to Expect)," 21 June 2020 Donald Trump doesn’t believe in gentlemen’s agreements, and his administration this week broke this one.
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The Economist, "Bello A gringo takeover bid for the Inter-American Development Bank," 20 June 2020 This one can be found on Lemmon Avenue where the Katy Trail passes overhead.
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Shannon Sutlief, Dallas News, "Take our photo quiz to test your knowledge of North Texas sights," 18 June 2020 Another shift – this one toward Jaap Stam's interpretation of the uptempo playing style –continued Wednesday as Stam and new assistant coach Said Bakkati joined the existing FC Cincinnati coaching staff for their second training session together.
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Pat Brennan, Cincinnati.com, "How FC Cincinnati is preparing for MLS is Back Tournament under Jaap Stam," 17 June 2020 This will be Woodward's second book about President Trump, who claims he was interviewed for this one.
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Mike Brest, Washington Examiner, "Bob Woodward's second Trump book to be released ahead of 2020 election," 17 June 2020
See MoreThese example sentences are selected automatically from various online news sources to reflect current usage of the word 'one.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
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Learn More about one
Watch More on one
Some Odd Words with ISMO: "The One-derful Won"
Comedian ISMO tries to figure out 'one' and 'two'
From the Editors at Merriam-Webster
A Countdown of Words with Numbers 10-1
A Countdown of Words with Numbers 10-1
From 'hang ten' to 'one-horse town'
Statistics for one
Look-up Popularity
Cite this Entry
“One.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/one. Accessed 8 Jul. 2020.
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More Definitions for one
one
adjectiveEnglish Language Learners Definition of one
(Entry 1 of 3)
: having the value of 1
—used to refer to a single person or thing
—used before a noun to indicate that someone or something is part of a group of similar people or things
one
nounEnglish Language Learners Definition of one (Entry 2 of 3)
: the number 1
US : a one-dollar bill
: one o'clock
one
pronounEnglish Language Learners Definition of one (Entry 3 of 3)
: that person or thing
: someone or something that is a part of a particular group
somewhat formal : people in general : any person
See the full definition for one in the English Language Learners Dictionary
one
adjective\ ˈwən \
\Kids Definition of one
(Entry 1 of 3)
1 : being a single unit or thing
There's one catch.
2 : being a certain unit or thing
He arrived early one morning.
3 : being the same in kind or quality
All the members of one class will sit together.
4 : not specified
We'll meet again one day.
one
nounKids Definition of one (Entry 2 of 3)
1 : the number denoting a single unit : 1
2 : the first in a set or series
3 : a single person or thing
one
pronounKids Definition of one (Entry 3 of 3)
1 : a single member or individual
I met one of your friends.
2 : any person
One never knows what will happen.
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Comments on one
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Time Traveler for one
The first known use of one was before the 12th century
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