undefined

adjective

ˌən-di-ˈfīnd How to pronounce undefined (audio)
Definition of undefinednext
as in vague
not seen or understood clearly plagued by undefined worries that kept her awake at night

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

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.
Recent Examples of undefined In a matter of minutes, my past and my still-undefined future crystallized. — Ayman M. Mohyeldin, Vanity Fair, 11 Sep. 2026 But the agreement subsequently collapsed as Washington and Tehran started fighting over shipping routes, which were left undefined in the deal. — Spencer Kimball,deena Zaidi, CNBC, 12 Aug. 2026 Still, despite the breakneck pace at which large language models and agentic AI are evolving, AI devices are still in the embryonic stage and very much undefined—a fact that may play to Ive’s strengths. — Emily Forlini, Fortune, 22 July 2026 Thanks to a particularly blurry playoff picture, many of the buyers and sellers remain undefined. — Patrick Mooney, New York Times, 16 July 2026 See All Example Sentences for undefined
Recent Examples of Synonyms for undefined
  1. vague
  2. faint
Adjective
  • Okay, Noah is somehow a Manhunter, though how this came to be is left vague and almost intangible for much of the episode.
    — Siddhant Adlakha, Vulture, 5 Oct. 2026
  • The law includes an exception for when a pregnant person’s life is in danger, but physicians and lawyers have said the language is vague and could be interpreted differently by different doctors and hospitals.
    — Ciara McCarthy October 5, Fort Worth Star-Telegram, 5 Oct. 2026
Definition of vague
Adjective
  • The concept uses single-photon lidar to detect faint laser reflections from an aircraft.
    — Aamir Khollam, Interesting Engineering, 30 Sep. 2026
  • This places the light on a more sensitive part of your retina and can make faint objects easier to see.
    — Daisy Dobrijevic, Space.com, 30 Sep. 2026
Definition of faint

Browse Nearby Words

undefinable
undefined
undeformed
See all Nearby Words

Cite this Entry

“Undefined.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undefined. Accessed 9 Oct. 2026.

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