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

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 Stocks and bonds have been in a simultaneous correction for the first time in decades. WSJ, 7 Aug. 2022 Kilar invested heavily in streaming during his tenure, including instituting simultaneous HBO Max and theatrical releases for Warner Bros. movies in 2021 and overseeing the launch of CNN+ — a platform that was swiftly axed by Zaslav's team. Daniel Arkin, NBC News, 4 Aug. 2022 As all nine stormed onto the survey dated Sept. 18, 2021, Drake also holds the mark for the most simultaneous top 10s. Gary Trust, Billboard, 4 Aug. 2022 But simultaneous outbreaks will compete for overlapping sets of resources, and put a subset of people at especially high peril of contracting both viruses, perhaps even in some cases simultaneously. Katherine J. Wu, The Atlantic, 4 Aug. 2022 There will also be simultaneous preview screenings of the film taking place at cinemas across the U.K. Naman Ramachandran, Variety, 3 Aug. 2022 Laporta was elected club president for a second time last year after his predecessor and the previous board were ousted for what amounted to the simultaneous financial and sporting collapse of one of the world’s great sports teams. New York Times, 3 Aug. 2022 The loss of Story was made more drastic by the simultaneous absence of Christian Arroyo. Alex Speier,, 31 July 2022 Speculation over the 91-year-old media executive’s thinking crescendoed after the first set of hearings concluded this month and two of his papers published nearly simultaneous editorials. Jeremy Barr, Washington Post, 30 July 2022 See More

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.

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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Dictionary Entries Near simultaneous



simultaneous contrast

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Last Updated

9 Aug 2022

Cite this Entry

“Simultaneous.” Dictionary, Merriam-Webster, Accessed 11 Aug. 2022.

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More Definitions for simultaneous


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

More from Merriam-Webster on simultaneous

Nglish: Translation of simultaneous for Spanish Speakers

Britannica English: Translation of simultaneous for Arabic Speakers


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