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 Almost simultaneous to the vote, Rudy Giuliani, the president’s personal lawyer, turned up at the White House. Jonathan Lemire, Twin Cities, "Trump calls impeachment vote ‘an embarrassment’ to nation," 13 Dec. 2019 Is that truly the case, or is there billionth-of-a-second microthread processing that just appears smooth and simultaneous? Caroline Delbert, Popular Mechanics, "The Coldest Chemical Reaction in the Known Universe Just Happened," 3 Dec. 2019 That big exhale, that feeling of simultaneous content and melancholy of a great night gone, is how TSHA’s music feels. Billboard Staff, Billboard, "Billboard Dance Emerging Artists: October 2019," 8 Oct. 2019 On the networking front, the HP Spectre x360 will have Wi-Fi 6 and optional gigabit LTE, with 4x4 antennas allowing for simultaneous gigabit Wi-Fi and LTE streaming and downloads. Ben Patterson, PCWorld, "Hands-on with HP’s new Spectre x360 13: Shrunk down and supercharged with Ice Lake," 30 Sep. 2019 Several leading experts on legal ethics have told me that Sessions’s simultaneous and dual roles almost certainly violated the American Bar Association’s Model Rules of Professional Conduct and federal government conflict of interest regulations. The New York Review of Books, "Murray Waas," 23 May 2019 For decades, the Beatles held the record with 14 simultaneous hits, an achievement that now ranks 17th behind Drake and others. Jo Craven Mcginty, WSJ, "Superstars Are Hogging Billboard’s Hot 100," 14 Dec. 2018 The facility also incorporates learnings from the simultaneous bombings in 1998 of the US embassies in Tanzania and Nairobi, which permanently altered the State Department’s presence overseas. Wired, "To Train Foreign Service Agents, You Must Build a Fake Town," 26 Nov. 2019 Disney's terms of service allow for four simultaneous streams on different devices, and seven different people can share a screen name. Jefferson Graham, USA TODAY, "Did Disney+ get hacked?," 18 Nov. 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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Time Traveler for simultaneous

Time Traveler

The first known use of simultaneous was circa 1660

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Statistics for simultaneous

Last Updated

13 Jan 2020

Cite this Entry

“Simultaneous.” The Dictionary, Merriam-Webster Inc., Accessed 24 January 2020.

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More Definitions for simultaneous


How to pronounce simultaneous (audio)

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 feeling of well-being or elation

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