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 simultaneously (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

But the Crown Prince’s attempts to cast himself as a modernizing reformer have been undermined by his simultaneous crackdowns on dissident voices, and mounting criticism of Saudi Arabia’s role in the disastrous war in Yemen. Joseph Hincks, Time, "Saudi Arabia Is Introducing Landmark Reforms for Women. But the Activists Who Pushed For Them Remain in Prison," 5 Aug. 2019 There and elsewhere across the Arctic, simultaneous and massive wildfires erupted, consuming millions of acres and emitting startling amounts of greenhouse gases. Author: Brady Dennis, Andrew Freedman, Anchorage Daily News, "July was the hottest month ever recorded. Here’s how it unfolded around the globe.," 5 Aug. 2019 In the afternoon, protesters have pledged to gather in seven different Hong Kong districts to hold simultaneous demonstrations. Ben Westcott, CNN, "Hong Kong protesters to march in Mong Kok, one of the world's most densely populated areas," 2 Aug. 2019 Heavy rain from a passing tropical wave will drench South Florida over the next two days, with the impact worsened in coastal neighborhoods by the simultaneous arrival of unusually high tides. David Fleshler,, "Heavy rain, high tides will make for a wet South Florida weekend," 1 Aug. 2019 An appearance by rapper Drake in 2018 pushed simultaneous Twitch viewers to a then-record of over 1 million, a very healthy number in an era when some of the most successful (and expensive) broadcast television shows draw around 6 million viewers. David Z. Morris, Fortune, "Ninja, Twitch’s Top Streamer, Leaves Amazon for Microsoft’s Mixer Streaming Platform," 1 Aug. 2019 Intel also enhanced its graphics quality as well as its performance, with support for three simultaneous 4K displays at 120Hz, a pair of 5K displays at 60Hz, or a single 8K30 display. Mark Hachman, PCWorld, "Intel launches 10th-gen 'Ice Lake' chips, pushing hard on graphics for notebook PCs," 1 Aug. 2019 One saving grace of these simultaneous slumps is that the two teams are well-matched. M.j., The Economist, "The Ashes will feature the weakest pair of cricket teams in decades," 31 July 2019 Rules require a simultaneous touch with both hands. David Woods, Indianapolis Star, "Lilly King disqualified in 200 breaststroke at worlds," 25 July 2019

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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Statistics for simultaneous

Last Updated

11 Aug 2019

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Time Traveler for simultaneous

The first known use of simultaneous was circa 1660

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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

What made you want to look up simultaneous? Please tell us where you read or heard it (including the quote, if possible).


a period when something is suspended

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