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 How a spouse chooses to inhabit a highly visible but largely undefined role is visually articulated through their fashion. — Anna Cafolla, Vogue, 25 Sep. 2026 An undefined position means scattershot and inconsistent AI usage at your company. — Rob Black, Forbes.com, 23 Sep. 2026 The role of the European Space Agency, perhaps NASA’s most enduring international partner, on the Moon Base program remains undefined. — Stephen Clark, ArsTechnica, 22 Sep. 2026 In a matter of minutes, my past and my still-undefined future crystallized. — Ayman M. Mohyeldin, Vanity Fair, 11 Sep. 2026 See All Example Sentences for undefined
Recent Examples of Synonyms for undefined
  1. vague
  2. faint
Adjective
  • Observers say the Student List party's policies remain vague, which has some worried about Serbia's future.
    — Chris Massaro, FOXNews.com, 27 Oct. 2026
  • Experts say the most successful devices aren’t those selling a vague wellness promise to optimize every aspect of a consumer’s health.
    — Amy O’Brien, Vogue, 27 Oct. 2026
Definition of vague
Adjective
  • This transition emits a faint radio wave at a wavelength of 21 centimeters.
    — Perri Thaler, Quanta Magazine, 30 Oct. 2026
  • From a genuinely dark location, M31 can be spotted with the naked eye as a faint patch.
    — Jamie Carter, Space.com, 30 Oct. 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 2 Nov. 2026.

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