instantaneous

adjective

ˌin(t)-stən-ˈtā-nē-əs How to pronounce instantaneous (audio)
Definition of instantaneousnext
as in immediate
done or occurring without any noticeable lapse in time the thunder following the flash of lightning was nearly instantaneous

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 instantaneous That transition is not instantaneous, and for a few minutes the two systems overlap. — Scott Travers, Forbes.com, 31 July 2026 Within the white space, high-density GPU racks require instantaneous, high-rate discharge to insulate servers against power spikes and dropouts. — Mrigakshi Dixit, Interesting Engineering, 27 July 2026 Wearing these items can give AI assistants instantaneous access to your life. — Lisa Eadicicco, CNN Money, 26 July 2026 The curse is that hundreds of LEO satellites are required to reliably provide near-instantaneous location and timing services across the entire world. — Jeremy Hsu, ArsTechnica, 16 July 2026 See All Example Sentences for instantaneous
Recent Examples of Synonyms for instantaneous
  1. immediate
  2. instant
Adjective
  • If a coyote behaves aggressively or poses an immediate threat to people, move to a safe location and call 911.
    — Todd Feurer, CBS News, 21 Aug. 2026
  • There was an immediate shift from Watts after the manic episode, McCollough’s friends say.
    — Cheyenne Roundtree, Rolling Stone, 20 Aug. 2026
Definition of immediate
Adjective
  • This photo taken on April 21, 2025 shows a customer walking past a display of instant noodles at a branch of Japanese discount retailer Don Quijote, also known overseas as Don Don Donki, in the Shibuya district of central Tokyo.
    — Lim Hui Jie, CNBC, 17 Aug. 2026
  • Set a realistic response time instead of snapping into instant availability.
    — Tarot.com, Sun Sentinel, 16 Aug. 2026
Definition of instant

Browse Nearby Words

instant
instantaneous
instantaneously
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Cite this Entry

“Instantaneous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/instantaneous. Accessed 23 Aug. 2026.

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More from Merriam-Webster on instantaneous

Nglish: Translation of instantaneous for Spanish Speakers

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