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simultaneous

[sahy-muhl-tey-nee-uhs, sim-uhl-]
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adjective

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

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RELATED WORDS

unanimity, synchronism, synchroneity

Origin of simultaneous

1650–60; < Latin simul together (see similar) + (instan)taneous
Related formssi·mul·ta·ne·ous·ly, adverbsi·mul·ta·ne·ous·ness, si·mul·ta·ne·i·ty [sahy-muhl-tuh-nee-i-tee, sim-uhl-] /ˌsaɪ məl təˈni ɪ ti, ˌsɪm əl-/, nounnon·si·mul·ta·ne·ous, adjectivenon·si·mul·ta·ne·ous·ly, adverbun·si·mul·ta·ne·ous, adjectiveun·si·mul·ta·ne·ous·ly, adverbun·si·mul·ta·ne·ous·ness, noun

Synonyms for simultaneous

SEE MORE SYNONYMS FOR simultaneous ON THESAURUS.COM
synchronous, coincident.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for simultaneity

Historical Examples of simultaneity

British Dictionary definitions for simultaneity

simultaneous

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 Formssimultaneously, 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
Word Origin and History for simultaneity
n.

1650s, from simultaneous + -ity.

simultaneous

adj.

1650s, from Medieval Latin simultaneus, perhaps from simultim "at the same time," extended from Latin simul "at the same time" (see similar (adj.)), or from simul with ending abstracted from Late Latin spontaneus, where the -t- is organic. Related: Simultaneously.

Online Etymology Dictionary, © 2010 Douglas Harper