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one

[wuhn] /wʌn/
adjective
1.
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.
2.
being a person, thing, or individual instance or member of a number, kind, group, or category indicated:
one member of the party.
3.
existing, acting, or considered as a single unit, entity, or individual.
4.
of the same or having a single kind, nature, or condition:
We belong to one team; We are of one resolve.
5.
noting some indefinite day or time in the future:
You will see him one day.
6.
a certain (often used in naming a person otherwise unknown or undescribed):
One John Smith was chosen.
7.
being a particular, unique, or only individual, item, or unit:
I'm looking for the one adviser I can trust.
8.
noting some indefinite day or time in the past:
We all had dinner together one evening last week.
9.
of no consequence as to the character, outcome, etc.; the same:
It's all one to me whether they go or not.
noun
10.
the first and lowest whole number, being a cardinal number; unity.
11.
a symbol of this number, as 1 or I.
12.
a single person or thing:
If only problems would come one at a time!
13.
a die face or a domino face having one pip.
14.
a one-dollar bill:
to change a five-dollar bill for five ones.
15.
(initial capital letter) Neoplatonism. 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.
pronoun
16.
a person or thing of a number or kind indicated or understood:
one of the Elizabethan poets.
17.
(in certain pronominal combinations) a person unless definitely specified otherwise:
every one.
18.
(with a defining clause or other qualifying words) a person or a personified being or agency:
the evil one; the one I love.
19.
any person indefinitely; anyone:
as good as one would desire.
20.
Chiefly British. (used as a substitute for the pronoun I):
Mother had been ailing for many months, and one should have realized it.
21.
a person of the speaker's kind; such as the speaker himself or herself:
to press one's own claims.
22.
something or someone of the kind just mentioned:
The portraits are fine ones. Your teachers this semester seem to be good ones.
23.
something available or referred to, especially in the immediate area:
Here, take one—they're delicious. The bar is open, so have one on me!
Idioms
24.
at one,
  1. in a state of agreement; of one opinion.
  2. united in thought or feeling; attuned:
    He felt at one with his Creator.
25.
one and all, everyone:
They came, one and all, to welcome him home.
26.
one by one, singly and successively:
One by one the children married and moved away.
27.
one for the road. road (def 9).
Origin
900
before 900; Middle English oon, Old English ān; cognate with Dutch een, German ein, Gothic ains, Latin ūnus (OL oinos); akin to Greek oínē ace on a die
Can be confused
one, wan, won (see usage note at the current entry)
Usage note
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 he1, they.

-one

1.
a suffix used in the names of ketones and analogous chemical compounds:
lactone; quinone.
Origin
perhaps < Greek -ōnē feminine patronymic
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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Examples for one
  • Individual action for the environment often calls for small acts, and recycling serves as one of the best examples of that.
  • The problem of evil is one of our oldest intellectual conundrums.
  • Whether it would be the last one up the engineers' sleeves, as the single-atom limit looms, remains to be seen.
  • one hundred and fifty people were found cast away on one island offshore.
  • one wonders if the churches are going to be able to find employment opportunities for all those new additions to the faith.
  • Variation is one of the basic elements that makes evolution possible.
  • So, our feathers have been ruffled lately by a nagging fear that one of our pullets is a rooster.
  • All of this may persuade no one who is still absorbed by this case.
  • How you want to weigh those different strengths will affect which one you end up choosing to work with.
  • The long one produces more transporter-protein molecules than the short one.
British Dictionary definitions for one

one

/wʌn/
determiner
1.
  1. single; lone; not two or more one car
  2. (as pronoun) one is enough for now, one at a time
  3. (in combination) one-eyed, one-legged
2.
  1. distinct from all others; only; unique one girl in a million
  2. (as pronoun) one of a kind
3.
  1. a specified (person, item, etc) as distinct from another or others of its kind raise one hand and then the other
  2. (as pronoun) which one is correct?
4.
a certain, indefinite, or unspecified (time); some one day you'll be sorry
5.
(informal) an emphatic word for a1 , an1 it was one hell of a fight
6.
a certain (person) one Miss Jones was named
7.
in one, all in one, combined; united
8.
all one
  1. all the same
  2. of no consequence it's all one to me
9.
(often foll by with) at one, in a state of agreement or harmony
10.
be made one, (of a man and a woman) to become married
11.
many a one, many people
12.
neither one thing nor the other, indefinite, undecided, or mixed
13.
never a one, none
14.
one and all, everyone, without exception
15.
one by one, one at a time; individually
16.
one or two, a few
17.
one way and another, on balance
18.
(informal) off on one, exhibiting bad temper; ranting
19.
one with another, on average
pronoun
20.
an indefinite person regarded as typical of every person one can't say any more than that
21.
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
22.
(archaic) an unspecified person one came to him
noun
23.
the smallest whole number and the first cardinal number; unity See also number (sense 1)
24.
a numeral (1, I, i, etc) representing this number
25.
(informal) a joke or story (esp in the one about)
26.
(music) the numeral 1 used as the lower figure in a time signature to indicate that the beat is measured in semibreves
27.
something representing, represented by, or consisting of one unit
28.
Also called one o'clock. one hour after noon or midnight
29.
a blow or setback (esp in the phrase one in the eye for)
30.
the one, (in Neo-Platonic philosophy) the ultimate being
31.
the Holy One, the One above, God
32.
the Evil One, Satan; the devil
related
prefixes mono- uni- adjective single
Word Origin
Old English ān, related to Old French ān, ēn, Old High German ein, Old Norse einn, Latin unus, Greek oinē ace

-one

suffix
1.
indicating that a chemical compound is a ketone acetone
Word Origin
arbitrarily from Greek -ōnē, feminine patronymic suffix, but perhaps influenced by -one in ozone
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for one
one
O.E. an, from P.Gmc. *ainaz (cf. O.N. einn, Dan. een, O.Fris. an, Du. een, Ger. ein, Goth. ains), from PIE *oinos (cf. Gk. oinos "ace (on dice)," L. unus "one," O.Pers. aivam, O.C.S. -inu, ino-, Lith. vienas, O.Ir. oin, Breton un "one"). Originally pronounced as it still is in only, and in dial. good 'un, young 'un, etc.; the now-standard pronunciation "wun" began c.14c. in southwest and west England (Tyndale, a Gloucester man, spells it won in his Bible translation), and it began to be general 18c. Use as indefinite pronoun influenced by unrelated Fr. on and L. homo. Slang one-arm bandit "a type of slot machine" is recorded by 1938. One-night stand is 1880 in performance sense; 1963 in sexual sense. One of the boys "ordinary amiable fellow" is from 1893. One-track mind is from 1927.
Online Etymology Dictionary, © 2010 Douglas Harper
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one in Medicine

-one suff.

  1. A ketone: acetone.

  2. A compound that contains oxygen, especially in a carbonyl radical: lactone.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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one in Science
-one  
A suffix used to form the names of chemical compounds containing an oxygen atom attached to a carbon atom, such as acetone.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Slang definitions & phrases for one

One

Related Terms

murder one, number one


The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D.
Copyright (C) 2007 by HarperCollins Publishers.
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Idioms and Phrases with one
The American Heritage® Idioms Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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3
4
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