si·mul·ta·neous | \ˌsī-məl-ˈtā-nē-əs, -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, -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

More than 30 households in the Ravinia neighborhood of Highland Park will hold simultaneous yard and garage sales from 9 a.m. to 3 p.m. July 14 and July 15. Karen Berkowitz,, "Shout Out: Francesca Kelly, mass yard sale organizer," 6 July 2018 Can’t wait to be queen Other species exhibit a type of hermaphroditism that is sequential, rather than simultaneous. Katherine J. Wu, Smithsonian, "Alternatives to Heterosexual Pairings, Brought to You By Non-Human Animals," 28 June 2018 Both Group A and Group B will be settled during simultaneous matches. Editors, USA TODAY, "World Cup, N.C. transgender battle and more things you need to know Monday," 25 June 2018 Argentina faces Nigeria in a simultaneous survival match in St. Petersburg on Tuesday. Derek Gatopoulos, The Seattle Times, "Iceland coach turns off cellphone to focus on Croatia," 25 June 2018 The research found that the simultaneous use of multiple drugs is becoming more common. NBC News, "Growing number of fatal car crashes linked to drug use," 3 June 2018 The album prompts seven debuts in the chart’s top 10, tying for the most simultaneous hits in the region since the chart began in 2012. Trevor Anderson, Billboard, "Drake Ties The Game For Most No. 1s on Top Rap Albums Chart," 13 July 2018 Encouraging the activity is a simultaneous boom in merger and initial public offering volume. Cara Lombardo, WSJ, "Activist Investors Turn Up Heat in Drive for Returns," 12 July 2018 Philadelphia rated favorably, but that may just be the simultaneous finding that our renters are less demanding than most. Shannon Rooney,, "What do Philly renters want most? Private laundry, air conditioning, parking," 9 July 2018

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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Last Updated

6 Oct 2018

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Time Traveler for simultaneous

The first known use of simultaneous was circa 1660

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English Language Learners Definition of simultaneous

: happening at the same time


si·mul·ta·neous | \ˌsī-məl-ˈtā-nē-əs \

Kids Definition of simultaneous

: existing or taking place at the same time simultaneous events

Other Words from simultaneous

simultaneously adverb

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