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 The collaboration made the announcement during a livestreamed press conference this morning from the European Southern Observatory's headquarters in Munich, Germany, as well as numerous other simultaneous press conferences around the world. Jennifer Ouellette, Ars Technica, 12 May 2022 The image, released in six simultaneous news conferences in Washington and around the globe, showed a lumpy doughnut of radio emission framing empty space. New York Times, 12 May 2022 Each subscription tier permits a certain number of simultaneous streams. Chris Smith, BGR, 25 Mar. 2022 That puts them on track for their biggest simultaneous drop in Dow Jones Market Data going back to 1976. Gunjan Banerji, WSJ, 3 May 2022 The Costume Institute’s simultaneous shows on American fashion coincide with its founding 75 years ago. Vogue, 29 Apr. 2022 The two most extensive invasion scenarios would involve a simultaneous attack from multiple sides — a maneuver known as a pincer movement or double envelopment. Courtney Kube, NBC News, 10 Feb. 2022 Johnson is, to an alarming degree, comfortable with multiple simultaneous truths and agendas. Sam Knight, The New Yorker, 4 Nov. 2021 Rather than attempting to resolve the essential crises of those vectors, Nelson’s essays tease out simultaneous and contradictory truths, or koans. Washington Post, 13 Sep. 2021 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

17 May 2022

Cite this Entry

“Simultaneous.” Dictionary, Merriam-Webster, Accessed 27 May. 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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