instantaneous

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

adjective

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·ta·ne·i·ty [in-stan-tn-ee-i-tee, in-stuhn-tuh-nee-] /ɪnˌstæn tnˈi ɪ ti, ˌɪn stən təˈni-/, in·stan·ta·ne·ous·ness, nounin·stan·ta·ne·ous·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for instantaneous

British Dictionary definitions for instantaneous

instantaneous

/ (ˌɪnstənˈteɪnɪəs) /

adjective

occurring with almost no delay; immediate
happening or completed within a momentinstantaneous death
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 zeroinstantaneous velocity

Derived Forms

instantaneously, adverbinstantaneousness or 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