[ im-pos-uh-buhl ]
/ ɪmˈpɒs ə bəl /
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See synonyms for: impossible / impossibly on Thesaurus.com


not possible; unable to be, exist, happen, etc.
unable to be done, performed, effected, etc.: an impossible assignment.
incapable of being true, as a rumor.
not to be done, endured, etc., with any degree of reason or propriety: an impossible situation.
utterly impracticable: an impossible plan.
hopelessly unsuitable, difficult, or objectionable.



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On the farm, the feed for chicks is significantly different from the roosters’; ______ not even comparable.

Origin of impossible

First recorded in 1250–1300; Middle English word from Latin word impossibilis.See im-2, possible
im·pos·si·ble·ness, nounim·pos·si·bly, adverb
impossible , impracticable, impractical, improbable
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for impossible

/ (ɪmˈpɒsəbəl) /


incapable of being done, undertaken, or experienced
incapable of occurring or happening
absurd or inconceivable; unreasonableit's impossible to think of him as a bishop
informal intolerable; outrageousthose children are impossible
impossibleness, nounimpossibly, adverb
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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