not, opposite of

Quick Summary

Prefixes are key morphemes in English vocabulary that begin words. A very large number of English vocabulary words contain the prefix un-, which means “not.” Examples using this prefix include unable, unfinished, and unsolved. An easy way to remember that the prefix un- means “not” is through the word unhappy, for if you are indeed unhappy you are “not” happy at all!

Unknotting "Un-" and "Not"!

Prefixes are key morphemes in English vocabulary that begin words. This podcast will untie the meaning of un- so that you shall “not” forget it!

Have you ever been unhappy or “not” happy because you were unable or “not” able to do something, hence leaving it unfinished or “not” done? Perhaps you found that to be unacceptable or “not” acceptable, and so you tried to do it, but the task became so unending or “not” ending that you had to leave it undone, or “not” completed? It would be nice if we could all be unaffected or “not” touched by things that we cannot do!

When visiting relatives, have you ever found something you were eating to be unappetizing, or “not” particularly suited to your tastes? Eating foods that you don’t like is probably unavoidable or “not” avoidable, especially when someone else is cooking for you! It is unlikely, however, or “not” likely that you’ll cook something for yourself that you don’t like, so volunteer to cook a meal or two!

Before doing a project for school, the idea of what it will end up being is originally unformed or has “not” taken shape. You may be uncertain or “not” sure about it for some time before realizing what you want it to be. From this point two things may happen: the project’s completion may remain unsolved because you were “not” able to figure out how to do it, or you may be so unerring or “not” wandering in your completion of the project that you get it done early!

Continuing this marvelous masterpiece of un- at this point would be unintentional on my part, so I’m going to unplug my computer at this very moment and “not” say anymore!

  1. unhappy: “not” happy
  2. unable: “not” able
  3. unfinished: “not” finished
  4. unacceptable: “not” acceptable
  5. unending: “not” ending
  6. undone: “not” done
  7. unaffected: “not” affected
  8. unappetizing: “not” suited to your taste in food
  9. unavoidable: “not” able to be avoided
  10. unlikely: “not” likely to happen
  11. unformed: “not” shaped
  12. uncertain: “not” certain
  13. unsolved: “not” solved
  14. unerring: “not” making a mistake
  15. unintentional: “not” intentional
  16. unplug: to “not” plug in for a longer time


  • uncharted

    Uncharted refers to something that has not been experienced before; it literally means that something has not been mapped out, and so remains an unknown.

  • unfeasible

    Something unfeasible cannot be made or achieved.

  • unseemly

    If you say someone's behavior is unseemly, you disapprove of it because it is not in good taste or not suitable for a particular situation.

  • unlettered

    If someone is unlettered, they are illiterate, unable to read and write.

  • untoward

    An untoward situation is something that is unfavorable, unfortunate, inappropriate, or troublesome.

  • unfazed

    To be unfazed is to not be affected by something that happens to you, even if it is quite embarrassing or bothersome.

  • uncouth

    To act in an uncouth manner is to be awkward and unmannerly.

  • unsavory

    If you describe something as unsavory, you mean that it is unpleasant or morally unacceptable.

  • unadorned

    Something that is unadorned is not made more attractive with ornament or decoration.

  • unremitting

    A thing or person that is unremitting is persistent and enduring in what is being done.

  • unkempt

    An unkempt person or thing is untidy and has not been kept neat.

  • unassuming

    Someone who is unassuming is not boastful or arrogant; rather, they are modest or humble.

  • unflagging

    If you are unflagging while doing a task, you are untiring when working upon it and do not stop until it is finished.

  • unobtrusive

    If someone acts in an unobtrusive way, their actions are not easily noticed and do not stand out in any way.

  • unrequited

    If you feel unrequited love for another, you love that person, but they don't love you in return.

  • unconscionable

    An action or deed is unconscionable if it is excessively shameful, unfair, or unjust and its effects are more severe than is reasonable or acceptable.

  • unprepossessing

    Something or someone that is unprepossessing is not impressive or is unattractive.

  • unsullied

    Something that is unsullied is unstained and clean.

  • unbridled

    A feeling that is unbridled is enthusiastic and unlimited in its expression.

  • unscathed

    To come out of something unscathed is to come out of it uninjured.

  • unalloyed

    Something that is unalloyed is whole or complete; for example, unalloyed pain cannot be relieved.

  • ungainly

    Someone who is ungainly is clumsy or awkward; something ungainly can be difficult to use, primarily because of its size or weight.

  • uncanny

    Something uncanny is very strange, unnatural, or highly unusual.

  • unflappable

    When you are unflappable, you remain calm, cool, and collected in even the most trying of situations.

  • unfounded

    An unfounded claim is not based upon evidence; instead, it is unproven or groundless.

  • unnerve

    If something unnerves you, it makes you upset or nervous; it can also make you lose your courage because it frightens you so much.

  • unorthodox

    An unorthodox opinion is unusual, not customary, and goes against established ways of thinking.

  • unparalleled

    An unparalleled accomplishment has not been equaled by anyone or cannot be compared to anything that anyone else has ever done.

  • unprecedented

    Something unprecedented has never occurred; therefore, it is unusual, original, or new.

  • unquenchable

    An unquenchable desire or thirst cannot be satisfied or gotten rid of.

  • unrelenting

    If you are unrelenting in your desire to do something, you stop at nothing until you've done it.

  • unrestrained

    Someone who is unrestrained is free to do as they please; they are not controlled by anyone but themselves, which can lead to excessive behavior.

  • unsightly

    An unsightly person presents an ugly, unattractive, or disagreeable face to the world.

  • unsurpassed

    If you are unsurpassed in what you do, you are the best—period.

  • unwarranted

    An unwarranted decision cannot be justified because there is no evidence to back it up; therefore, it is needless and uncalled-for.

  • unwieldy

    Something that is unwieldy is hard or awkward to handle because of the way that it is shaped.

  • unwitting

    If you do something in an unwitting fashion, you didn't know that you were doing it; therefore, it was unintentional on your part.

  • unbiased

    Someone who has an unbiased opinion of another does not unfairly judge, but is fair and just in his consideration of that person.

  • unprincipled

    An unprincipled person is immoral, not ethical, or dishonest; therefore, they often do things that are wrong.

  • unstable

    Something unstable, such as a building or government, is not strong and has problems; therefore, it can change suddenly for the worse or fail in some way.

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