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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 But his son went to meet Kaya, and the connection was almost instantaneous. — Alicia Urrea, Billboard, 27 Aug. 2026 And all have been just as vulnerable to the near-instantaneous bootlegging. — Gene Maddaus, Variety, 21 Aug. 2026 In his Missouri Western dormitory office on Wednesday morning, Reid acknowledged an instantaneous turn toward 2026. — Kansas City Star, 19 Aug. 2026 The effects feel nearly instantaneous thanks to the addition of cica, hyaluronic acid, and shea butter, which results in a calm, cooling sensation. — Mary Honkus, Glamour, 18 Aug. 2026 See All Example Sentences for instantaneous
Recent Examples of Synonyms for instantaneous
  1. immediate
  2. instant
Adjective
  • His bold, unique style was an immediate hit with ad agencies, publications, the corporate world and in pop culture.
    — BETH J. HARPAZ THE ASSOCIATED PRESS, Arkansas Online, 18 Sep. 2026
  • Pressuring currencies One of the most immediate channels through which a tighter Fed policy travels around the world is the dollar.
    — Lee Ying Shan, CNBC, 17 Sep. 2026
Definition of immediate
Adjective
  • The patented multi-panel high-rise waistband technology in the leggings boosts muscle memory in core, glutes, and spine for instant alignment, stability, support and pain relief.
    — ABC News, ABC News, 14 Sep. 2026
  • In practice, though, victims of instant-payment fraud often recover little.
    — Pawan Jain, The Conversation, 14 Sep. 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 18 Sep. 2026.

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