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

Despite instantaneous, zero-fee transactions, the explosion of exchange-traded funds, and algorithmic trading, the economic role of the U.S. public markets has been in quiet retreat.

From Barron's

The unique combination of instantaneous torque, lightweight powertrain and low center of gravity—due to the placement of those heavy batteries—means these vehicles have the potential to be something akin to street-legal Indy cars.

From The Wall Street Journal

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

Related Words

• rapid
• spontaneous
• transitory