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simultaneous

[ sahy-muhl-tey-nee-uhs, sim-uhl- ]
/ ˌsaɪ məlˈteɪ ni əs, ˌsɪm əl- /
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See synonyms for: simultaneous / simultaneity / simultaneously / simultaneousness on Thesaurus.com

adjective
existing, occurring, or operating at the same time; concurrent: simultaneous movements;simultaneous translation.
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Origin of simultaneous

First recorded in 1650–60; from Latin simul “together” (see similar) + (instan)taneous

OTHER WORDS FROM simultaneous

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use simultaneous in a sentence

British Dictionary definitions for simultaneous

simultaneous
/ (ˌsɪməlˈteɪnɪəs, US ˌsaɪməlˈteɪnɪəs) /

adjective
occurring, existing, or operating at the same time; concurrent
noun
chess a display in which one player plays a number of opponents at once, walking from board to boardSometimes shortened to: simul

Derived forms of simultaneous

simultaneously, adverbsimultaneousness or simultaneity (ˌsɪməltəˈniːɪtɪ, US ˌsaɪməltəˈniːɪtɪ), noun

Word Origin for simultaneous

C17: formed on the model of instantaneous from Latin simul at the same time, together
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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