un·​de·​cid·​able ˌən-di-ˈsī-də-bəl How to pronounce undecidable (audio)
: not capable of being decided : not decidable
… a huge popular audience, most of whom must have been baffled and exasperated by its elaborate and undecidable mystifications.David Lodge
deconstruction, which teaches that literature is essentially "undecidable," beyond interpretation …James Atlas
To be complete such a system must be able to prove that any formula expressible in its language (a mathematical equation, for example, or a statement in symbolic logic) is either true or false; nothing can be undecidable.George Johnson
undecidability noun

Examples of undecidable in a Sentence

Recent Examples on the Web Only a few years after Kurt Gödel had proved that mathematics was incomplete, Church and Turing showed with this work that some problems in mathematics are undecidable — no algorithm, however sophisticated, can tell us whether the answer is yes or no. Sheon Han, Quanta Magazine, 3 May 2023 But these, too, can turn out to be undecidable, since one set of interpreters can ascertain an implicit right to privacy, which is invisible to another—or even an explicit right to private ownership of guns, which has been invisible to every preceding set of interpreters. Adam Gopnik, The New Yorker, 26 Nov. 2021 Could a statement about a single tile also be undecidable? Jordana Cepelewicz, Quanta Magazine, 15 Dec. 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'undecidable.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1640, in the meaning defined above

Time Traveler
The first known use of undecidable was in 1640

Dictionary Entries Near undecidable

Cite this Entry

“Undecidable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undecidable. Accessed 5 Dec. 2023.

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