instantaneous

American  

[in-stuhn-tey-nee-uhs] / ˌɪn stənˈteɪ ni əs /

adjective

1. occurring, done, or completed in an instant.

   an instantaneous response.

   Synonyms:

   abrupt, sudden, immediate

2. existing at or pertaining to a particular instant.

   the instantaneous position of the rocket.

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instantaneous British  

/ ˌɪnstənˈteɪnɪəs, ɪnˌstæntəˈniːɪtɪ /

adjective

1. occurring with almost no delay; immediate

2. happening or completed within a moment

   instantaneous death

3. maths

   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

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Other Word Forms

• instantaneity noun
• instantaneously adverb
• instantaneousness noun

Etymology

Origin of instantaneous

From the Medieval Latin word instantāneus, dating back to 1645–55. See instant, -an, -eous

Example Sentences

He recalled "a terrific flash of lightning and almost instantaneous crash of thunder, which woke quite a few people up - and probably frightened Father Christmas".

From BBC

While the Eaton fire disaster was instantaneous, the loss of such a deep-rooted community in Altadena has happened much slower, over thousands of private decisions.

From Los Angeles Times

The proposal garnered instantaneous backlash from American cattle producers.

From Los Angeles Times

Where “Eusexua” is “the bird’s eye view of the human experience,” Twigs says, “Afterglow” is meant to capture humanity through a more direct lens, where feelings are unfiltered and instantaneous.

From Los Angeles Times

In what amounted to an instantaneous confidence boost, Lateef took off running on his team’s first play from scrimmage and spun his way for 14 yards.

From Los Angeles Times

Related Words

• rapid
• spontaneous
• transitory