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90s Slang You Should Know


[in-stuh n-tey-nee-uh s] /ˌɪn stənˈteɪ ni əs/
occurring, done, or completed in an instant:
an instantaneous response.
existing at or pertaining to a particular instant:
the instantaneous position of the rocket.
Origin of instantaneous
From the Medieval Latin word instantāneus, dating back to 1645-55. See instant, -an, -eous
Related forms
[in-stan-tn-ee-i-tee, in-stuh n-tuh-nee-] /ɪnˌstæn tnˈi ɪ ti, ˌɪn stən təˈni-/ (Show IPA),
instantaneousness, noun
instantaneously, adverb
1. immediate, sudden, abrupt. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2017.
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Examples from the Web for instantaneous
Contemporary Examples
Historical Examples
  • Then, by an instantaneous revulsion, the grim humour of the situation struck me.

  • Trembling with excitement, Harry did as he was told; the result was instantaneous.

  • Its success was instantaneous, though neither the Puritans nor Mr. Pepys could quite see the joke.

    The Age of Dryden Richard Garnett
  • So the explosion of popular indignation was instantaneous and terrible.

    The Story of Rouen Sir Theodore Andrea Cook
  • Their smiles and glances met each other with an instantaneous understanding.

    Remember the Alamo Amelia E. Barr
  • At all hazards I would protect them—such was my instantaneous determination.

    Fibble, D. D. Irvin Shrewsbury Cobb
British Dictionary definitions for instantaneous


occurring with almost no delay; immediate
happening or completed within a moment: instantaneous death
  1. occurring at or associated with a particular instant
  2. equal to the limit of the average value of a given variable as the time interval over which the variable is considered approaches zero: instantaneous velocity
Derived Forms
instantaneously, adverb
instantaneousness, instantaneity (ɪnˌstæntəˈniːɪtɪ) noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for instantaneous

1640s (implied in instantaneously), formed in English from Medieval Latin *instantaneus, from instantem (see instant (n.)) on model of spontaneous. Related: Instantaneousness.

Online Etymology Dictionary, © 2010 Douglas Harper
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