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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.

El Team Stars, el primer equipo en anotar cinco puntos en la prórroga, ganó 37-35 con un triple de Scottie Barnes.

From Los Angeles Times • Feb. 15, 2026

A sus 41 años y jugando su 23ª temporada, un récord, se le preguntó a James sobre su futuro, ya que su eventual retirada siempre parece ser motivo de curiosidad.

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

Los equipos especiales han sido la pesadilla de McVay durante un par de años.

From Los Angeles Times • Jan. 26, 2026

Learning that the house he coveted was un available for rent but up for sale, he bought it on the spot.

From "Big Science" by Michael Hiltzik