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un

1 American  
[uhn] / ən /
Or 'un

pronoun

Dialect.
  1. one.

    young uns; He's a bad un.


UN 2 American  
Or U.N.

abbreviation

  1. United Nations.


un- 3 American  
  1. a prefix meaning “not,” freely used as an English formative, giving negative or opposite force in adjectives and their derivative adverbs and nouns (unfair; unfairly; unfairness; unfelt; unseen; unfitting; unformed; unheard-of; un-get-at-able ), and less freely used in certain other nouns (unrest; unemployment ).


un- 4 American  
  1. a prefix freely used in English to form verbs expressing a reversal of some action or state, or removal, deprivation, release, etc. (unbend; uncork; unfasten , etc.), or to intensify the force of a verb already having such a meaning (unloose ).


un- 1 British  

prefix

  1. denoting reversal of an action or state

    uncover

    untangle

  2. denoting removal from, release, or deprivation

    unharness

    unman

    unthrone

  3. (intensifier)

    unloose

"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

UN 2 British  

abbreviation

  1. United Nations

"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

'un 3 British  
/ ən /

pronoun

  1. a spelling of one

    that's a big 'un

"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

un- 4 British  

prefix

  1. (freely used with adjectives, participles, and their derivative adverbs and nouns: less frequently used with certain other nouns) not; contrary to; opposite of

    uncertain

    uncomplaining

    unemotionally

    untidiness

    unbelief

    unrest

    untruth

"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

Usage

This spelling is intended to reflect a dialectal or informal pronunciation

Related Words

See in- 3.

Etymology

Origin of un-3

Middle English un-, on-, Old English; cognate with Dutch on-, Gothic, German un-, Old Norse ū-, ō-; akin to Latin in-, Greek an-, a-. See a- 6, an- 1, in- 3

Origin of un-4

Middle English, Old English un-, on-; cognate with Gothic and-, Dutch ont-, German ent-; akin to Latin ante, Greek antí; ante-, anti-

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Y vuelven a ser All-Stars, todos mayores de 37 años y aún jugando a un alto nivel.

From Los Angeles Times • Feb. 15, 2026

“Siempre es un honor ver a esos chicos”, dijo James.

From Los Angeles Times • Feb. 15, 2026

“Este ha sido un año especial, es difícil asimilar que se haya acabado”.

From Los Angeles Times • Jan. 26, 2026

Esta vez fue Xavier Smith quien falló un punt y Dareke Young lo recuperó en la yarda 17 de los Rams.

From Los Angeles Times • Jan. 26, 2026

“So how did it go down? Tell me everything. C'était un surprise,” I add as Madame Blanc makes her way up my row.

From "Simon vs. the Homo Sapiens Agenda" by Becky Albertalli