being or amounting to a single unit or individual or entire thing, item, or object rather than two or more; a single.
one woman;
one nation;
one piece of cake.
being a person, thing, or individual instance or member of a number, kind, group, or category indicated.
one member of the party.
existing, acting, or considered as a single unit, entity, or individual.
of the same or having a single kind, nature, or condition: We are of one resolve.
We belong to one team.
We are of one resolve.
noting some indefinite day or time in the future.
You will see him one day.
a certain (often used in naming a person otherwise unknown or undescribed).
One John Smith was chosen.
being a particular, unique, or only individual, item, or unit.
I'm looking for the one adviser I can trust.
noting some indefinite day or time in the past.
We all had dinner together one evening last week.
of no consequence as to the character, outcome, etc.; the same.
It's all one to me whether they go or not.
the first and lowest whole number, being a cardinal number; unity.
a symbol of this number, as 1 or I.
a single person or thing.
If only problems would come one at a time!
a die face or a domino face having one pip.
a one-dollar bill.
to change a five-dollar bill for five ones.
Philosophy. One. (inNeoplatonism ) the ultimate reality, seen as a central source of being by whose emanations all entities, spiritual and corporeal, have their existence, the corporeal ones containing the fewest of the emanations.
a person or thing of a number or kind indicated or understood.
one of the Elizabethan poets.
(in certain pronominal combinations) a person unless definitely specified otherwise.
every one.
(with a defining clause or other qualifying words) a person or a personified being or agency: the one I love.
the evil one;
the one I love.
any person indefinitely; anyone.
One's score is never as good as one would desire.
Chiefly British. (used as a substitute for the pronoun I).
Mother had been ailing for many months, and one should have realized it.
a person of the speaker's kind; such as the speaker's own self.
to press one's own claims.
something or someone of the kind just mentioned: Your teachers this semester seem to be good ones.
The portraits are fine ones.
Your teachers this semester seem to be good ones.
something available or referred to, especially in the immediate area: The bar is open, so have one on me!
Here, take one—they're delicious.
The bar is open, so have one on me!
single; lone; not two or more
one car
( as pronoun )
one is enough for now
one at a time
( in combination )
one-eyed
one-legged
distinct from all others; only; unique
one girl in a million
( as pronoun )
one of a kind
a specified (person, item, etc) as distinct from another or others of its kind
raise one hand and then the other
( as pronoun )
which one is correct?
a certain, indefinite, or unspecified (time); some
one day you'll be sorry
informal an emphatic word for a 1 an 1
it was one hell of a fight
a certain (person)
one Miss Jones was named
combined; united
all the same
of no consequence
it's all one to me
(often foll by with) in a state of agreement or harmony
(of a man and a woman) to become married
many people
indefinite, undecided, or mixed
none
everyone, without exception
one at a time; individually
a few
on balance
informal exhibiting bad temper; ranting
on average
an indefinite person regarded as typical of every person
one can't say any more than that
any indefinite person: used as the subject of a sentence to form an alternative grammatical construction to that of the passive voice
one can catch fine trout in this stream
archaic an unspecified person
one came to him
the smallest whole number and the first cardinal number; unity See also number
a numeral (1, I, i, etc) representing this number
informal a joke or story (esp in the one about )
music the numeral 1 used as the lower figure in a time signature to indicate that the beat is measured in semibreves
something representing, represented by, or consisting of one unit
Also called: one o'clock. one hour after noon or midnight
a blow or setback (esp in the phrase one in the eye for )
(in Neo-Platonic philosophy) the ultimate being
God
Satan; the devil
One as an indefinite pronoun meaning “any person indefinitely, anyone” is more formal than you, which is also used as an indefinite pronoun with the same sense: One (or you ) should avoid misconceptions. One (or you ) can correct this fault in three ways. When the construction requires that the pronoun be repeated, either one or he or he or she is used; he or he or she is the more common in the United States: Wherever one looks, he (or he or she ) finds evidence of pollution. In speech or informal writing, a form of they sometimes occurs: Can one read this without having their emotions stirred? In constructions of the type one of those who (or that or which ), the antecedent of who is considered to be the plural noun or pronoun, correctly followed by a plural verb: He is one of those people who work for the government. Yet the feeling that one is the antecedent is so strong that a singular verb is commonly found in all types of writing: one of those people who works for the government. When one is preceded by only in such a construction, the singular verb is always used: the only one of her sons who visits her in the hospital. The substitution of one for I, a typically British use, is usually regarded as an affectation in the United States. See also he 1, they.
First recorded before 900; Middle English oon, Old English ān; cognate with Dutch een, German ein, Gothic ains, Latin ūnus ( Old Latin oinos ); akin to Greek oínē “ace on a die”
Perhaps < Greek -ōnē feminine patronymic
One refers to a single person or thing, as well as the number one. If you’re looking for a whole number between zero and two, you can only find one. One is all alone, but it at least it gets to be the first in line. It also gets to be the one and only, far and away the best, and one of a kind. If something (or someone) is "the one" you’ve been looking for, it’s exactly what you want. Sometimes one actually refers to more than one person being united in some way; if you and your friend are of "one mind," you think alike about something.
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Don’t use your sous-vide bath, should you be so fortunate as to have one, cooking the steak for hours until it reaches the desired temperature and then finishing with a quick sear.
From The Wall Street Journal ● Jul. 23, 2026
For me, one of the more emotional ones last year was Rise Against.
From Los Angeles Times ● Jul. 23, 2026
And one of the most thorough goings-over Ms. Lam gives is to the singular steak and how to perfectly prepare one.
From The Wall Street Journal ● Jul. 23, 2026
To be honest, I knew I had one shot at getting it right.
From Los Angeles Times ● Jul. 23, 2026
He leans his shoulder against one of the posts outside the Pioneer Saloon.
From "Will’s Race for Home" by Jewell Parker Rhodes
The government also promised to strengthen enforcement against illegal burning -one of the main causes of wildfires - and crack down on individual carelessness.
From BBC ● Mar. 26, 2025
The suffix, -one, changes the meaning to “large cake.”
From New York Times ● Dec. 20, 2021
The names for aldehyde and ketone compounds are derived using similar nomenclature rules as for alkanes and alcohols, and include the class-identifying suffixes -al and -one, respectively:
From Textbooks ● Feb. 14, 2019
Others thought they would never see the day that in conservative Idaho -one of the most Republican-dominated states in the nation- same-sex marriage would be legalized.
From Washington Times ● Dec. 28, 2014
Renn came after him, backing out on hands and knees and dragging two hazelwood packs -one of them his own.
From "Wolf Brother" by Michelle Paver
There are now two such vaccines –one made by Merck, another by Johnson & Johnson.
From The Guardian ● May 18, 2018
Residents have to sweep away the dead ones on the ground day after day.
From Los Angeles Times ● Jul. 23, 2026
Men aren’t the only ones disappointed in the president’s performance.
From Slate ● Jul. 23, 2026
These measures were proposed after a months-long investigation and are considered more durable than earlier ones.
From Barron's ● Jul. 23, 2026
At the 20% tax rate, that is about $18 million more than he would have had if he had instead made the 2021 sale—and a series of smaller ones this year—in a taxable brokerage account.
From The Wall Street Journal ● Jul. 22, 2026
But I can’t figure out which ones I want to write about or what I’d want to “say.”
From "Keeping Pace" by Laurie Morrison
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
