undefined

adjective

un·​de·​fined ˌən-di-ˈfīnd How to pronounce undefined (audio)
: not defined: such as
a
: not clearly or precisely shown, described, or limited
undefined rules
undefined powers
a vague, undefined feeling of dread
… the true outlines of Clinton's foreign policy remain undefined.William Greider
b
: not provided with a definition
an undefined dictionary entry

Examples of undefined in a Sentence

plagued by undefined worries that kept her awake at night
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The first phase leaves Hamas armed and operational, doesn’t guarantee disarmament or leadership exile, and Gaza’s post-war governance remains undefined. Tal Shalev, CNN Money, 11 Oct. 2025 This year, Wisconsin (2-3) is struggling, while Iowa (3-2) remains undefined. Scott Dochterman, New York Times, 10 Oct. 2025 Prosecutors say in court papers that Hoffman was fully aware he was prohibited from funneling hundreds of thousands of dollars in undefined, but did so anyway. Chris Ramirez, jsonline.com, 25 Sep. 2025 But with many terms still undefined, small business owners must be nimble—leveraging digital tools, planning for financial flexibility, and preparing for multiple scenarios to stay ahead. Eric Youngstrom, Forbes.com, 8 Sep. 2025 See All Example Sentences for undefined

Word History

First Known Use

1611, in the meaning defined above

Time Traveler
The first known use of undefined was in 1611

Browse Nearby Words

Cite this Entry

“Undefined.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undefined. Accessed 24 Oct. 2025.

Last Updated: - Updated example sentences
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