Something that's impossible can't be done. If you want to stop eating donuts but you just can't, you might say it's impossible.

If it's impossible, it cannot happen, or it doesn't exist. You might wish you could bring Abraham Lincoln back to life for a day so he could come to tea, but that's impossible. People use the word impossible to mean "out of reach" or "too hard to achieve." A terrible situation can be impossible, and so can a person who refuses to compromise or seems intent on making things difficult for everyone else.

Definitions of impossible
  1. adjective
    not capable of occurring or being accomplished or dealt with
    “an impossible dream”
    “an impossible situation”
    without hope because there seems to be no possibility of comfort or success
    certain to fail
    impracticable, infeasible, unfeasible, unworkable
    not capable of being carried out or put into practice
    not worth considering as a possibility
    unachievable, unattainable, undoable, unrealizable
    impossible to achieve
    not practical; not workable or not given to practical matters
    not realistic
    insurmountable, unsurmountable
    not capable of being surmounted or overcome
    incapable of being conceived or considered
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    capable of happening or existing
    having a good chance of being the case or of coming about
    accomplishable, achievable, doable, manageable, realizable
    capable of existing or taking place or proving true; possible to do
    affirmable, assertable
    capable of being affirmed or asserted
    attainable, come-at-able
    capable of being attained or accomplished
    possible but not certain to occur
    executable, feasible, practicable, viable, workable
    capable of being done with means at hand and circumstances as they are
    statistically possible though highly improbable
    concerned with actual use or practice
    aware or expressing awareness of things as they really are
    capable of being conceived or imagined or considered
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  2. adjective
    totally unlikely
    synonyms: inconceivable, out of the question, unimaginable
    incapable of being conceived or considered
  3. noun
    something that cannot be done
    “his assignment verged on the impossible
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    type of:
    impossibility, impossible action
    an alternative that is not available
  4. adjective
    used of persons or their behavior
    impossible behavior”
    synonyms: insufferable, unacceptable, unsufferable
    intolerable, unbearable, unendurable
    incapable of being put up with
Word Family

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