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

But we live in an era when instantaneous certitude about everything, an iron conviction in subjective judgment in the face of objective uncertainty, is the only guarantee of a hearing.

From The Wall Street Journal

“Access to the classical studies is now instantaneous: literature, science, art, philosophy, mathematics and history.”

From Salon

"Imagine a humanoid educator named Plato. Access to the classical studies is now instantaneous," she said.

From Barron's

In some cases, Wall Street banks shut off electronic systems that offer instantaneous quotes to investors looking to buy or sell bonds.

From The Wall Street Journal

The entire NFL had the same instantaneous reaction: What in the name of John Madden was going on?

From The Wall Street Journal

Related Words

• rapid
• spontaneous
• transitory