si·​mul·​ta·​neous | \ ˌsī-məl-ˈtā-nē-əs How to pronounce simultaneous (audio) , -nyəs also ˌsi- \

Definition of simultaneous

1 : existing or occurring at the same time : exactly coincident
2 : satisfied by the same values of the variables simultaneous equations

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Other Words from simultaneous

simultaneity \ ˌsī-​məl-​tə-​ˈnē-​ə-​tē , -​ˈnā-​ also  ˌsi-​ \ noun
simultaneously \ ˌsī-​məl-​ˈtā-​nē-​əs-​lē How to pronounce simultaneous (audio) , -​nyəs-​ also  ˌsi-​ \ adverb
simultaneousness noun

Choose the Right Synonym for simultaneous

contemporary, contemporaneous, coeval, synchronous, simultaneous, coincident mean existing or occurring at the same time. contemporary is likely to apply to people and what relates to them. Abraham Lincoln was contemporary with Charles Darwin contemporaneous is more often applied to events than to people. contemporaneous accounts of the kidnapping coeval refers usually to periods, ages, eras, eons. two stars thought to be coeval synchronous implies exact correspondence in time and especially in periodic intervals. synchronous timepieces simultaneous implies correspondence in a moment of time. the two shots were simultaneous coincident is applied to events and may be used in order to avoid implication of causal relationship. the end of World War II was coincident with a great vintage year

Examples of simultaneous in a Sentence

The two gunshots were simultaneous. a simultaneous release of the movie and its soundtrack on CD
Recent Examples on the Web This surge in interest in learning and playing music has resulted in a simultaneous surge in sales of musical instruments. Richard A. Marini, San Antonio Express-News, "More people are picking up old instruments and making beautiful music again thanks to the COVID-19 pandemic," 5 Feb. 2021 The minutiae and microaggressions add up to a terrific little one-act comedy, and maybe that’s the city incarnate: millions of simultaneous, overlapping one-acts fighting for better billing in America’s messiest street festival. Michael Phillips,, "‘City So Real’ review: A sobering Chicago symphony in five movements, on Hulu and National Geo," 28 Oct. 2020 There were more than 100 of these simultaneous transactions following lease awards in the past 25 years, according to the analysis. Promised Land, ProPublica, "To Reclaim Ancestral Land, All Native Hawaiians Need Is a $300,000 Mortgage and to Wait in Line for Decades," 26 Oct. 2020 But simultaneous face and double hand transplants are extremely rare and have only been tried twice before. Star Tribune, "'New chance at life': Man gets face, hands in rare surgery," 2 Feb. 2021 His sudden promotion sent simultaneous messages, not only about the rookie’s positive contribution in limited time but also foreshadowed where this Pelicans’ season is likely headed. Scott Kushner,, "Kushner: Kira Lewis Jr.'s time has finally come at turning point in Pelicans' season," 2 Feb. 2021 His simultaneous confusion, terror, and shame feel genuine. John Roy, Vulture, "Nick Vatterott’s Late-Night Debut Brilliantly Tests the Audience’s Comfort," 2 Feb. 2021 With Vice President Kamala Harris serving as tie-breaker, the Democrats managed to secure a functional majority in the Senate—and with it, simultaneous control over Congress and the White House by the thinnest of margins. Matt Ford, The New Republic, "Mitch McConnell Is Killing the Filibuster," 23 Jan. 2021 The urgency to hold Trump responsible is somewhat complicated by Democrats' simultaneous need to get Biden's government in place and start quick work on his coronavirus aid package. Mary Clare Jalonick And Lisa Mascaro, Chron, "Schumer: Trump impeachment trial to begin week of Feb. 8," 22 Jan. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'simultaneous.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of simultaneous

circa 1660, in the meaning defined at sense 1

History and Etymology for simultaneous

Latin simul at the same time + English -taneous (as in instantaneous) — more at same

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Time Traveler for simultaneous

Time Traveler

The first known use of simultaneous was circa 1660

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Statistics for simultaneous

Last Updated

22 Feb 2021

Cite this Entry

“Simultaneous.” Dictionary, Merriam-Webster, Accessed 28 Feb. 2021.

Style: MLA
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More Definitions for simultaneous



English Language Learners Definition of simultaneous

: happening at the same time


si·​mul·​ta·​neous | \ ˌsī-məl-ˈtā-nē-əs How to pronounce simultaneous (audio) \

Kids Definition of simultaneous

: existing or taking place at the same time simultaneous events

Other Words from simultaneous

simultaneously adverb

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Comments on simultaneous

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