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

With the power of Google's cloud behind them, Stadia games could revolve around feats of computing no current home-console could ever hope to accomplish, like 8K resolution or thousands of simultaneous players in the same game. Eric Limer, Popular Mechanics, "Google's 'Stadia' Is the Latest Attack in the War on Games You Can Actually Own," 19 Mar. 2019 For updates from the other simultaneous Group H finale between Japan and Poland, read on here. Avi Creditor,, "LIVE: Senegal, Colombia Battle for Knockout Stage Place in World Cup," 28 June 2018 Today marks the 67th anniversary of these simultaneous world events: King George VI’s death, and Queen Elizabeth’s ascension day. Elise Taylor, Vogue, "For Queen Elizabeth, February 6th Has a Special—and Complicated—Meaning," 6 Feb. 2019 Minutes later, fans cheered as Musk topped himself by nailing a simultaneous landing of the Falcon Heavy's boosters. Justin Bachman,, "SpaceX, other private launches mess with airline schedules," 2 July 2018 If everything goes off without a hitch, the most exciting part of the test launch should be the simultaneous landings of the two side boosters on land, followed by the landing of the center core on a drone ship at sea. Jay Bennett, Popular Mechanics, "15 Air and Space Missions We're Excited for In 2018," 5 Jan. 2018 And with cameras positioned all over the rocket, viewers got to witness every single aspect of the flight — including the launch, the simultaneous landing of the two outer boosters, and the mannequin’s cruise through Earth orbit. Loren Grush, The Verge, "The Verge 2018 tech report card: SpaceX," 29 Dec. 2018 Other than a fresh locale, the big changes for FH4 are in the number of simultaneous players—now up to 72 in a session—and seasonal transitions that join dynamic day-to-night-to day lighting and dynamic weather to keep the place looking fresh. Kyle Orland, Ars Technica, "Ars Technica’s best games of 2018," 24 Dec. 2018 The outflows come as a record share of asset classes including stocks, bonds, commodities and currencies are down this year, a rare simultaneous retreat across Wall Street that has prompted investors to direct their money elsewhere. Steven Russolillo, WSJ, "The Worst Redemptions on Record Add to Global Markets’ Pain," 18 Dec. 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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Statistics for simultaneous

Last Updated

24 Mar 2019

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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 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).


marked by a state of overwhelming emotion

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