simultaneous

adjective si·mul·ta·neous \ ˌsī-məl-ˈtā-nē-əs , -nyəs also ˌsi- \

Updated on: 8 Apr 2018

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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simultaneity

\ˌsī-məl-tə-ˈnē-ə-tē, -ˈnā- also ˌsi-\ noun

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simultaneously

play \ˌsī-məl-ˈtā-nē-əs-lē, -nyəs- also ˌsi-\ adverb

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simultaneousness

noun

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Examples of simultaneous in a Sentence

The two gunshots were simultaneous.
a simultaneous release of the movie and its soundtrack on CD

Recent Examples of simultaneous from the Web

However, maybe because of the simultaneous Easter holiday, there didn't appear to be as many jokes as in previous years.

— carly mallenbaum, USA TODAY, "Joking! Lin-Manuel Miranda, Seth Rogen prank the Internet for April Fool's Day," 1 Apr. 2018
Its military doctrine envisages fighting simultaneous land wars against Pakistan and China while retaining dominance in the Indian Ocean.

— The Economist, "India spends a fortune on defence and gets poor value for money," 28 Mar. 2018
One that usually involves the violation of - the simultaneous violation of dozens of laws.

— Fox News, "Sen. Mike Lee: Budget process is bad for the American people," 26 Mar. 2018
But that misstep is entirely overshadowed by one of the video’s final images: the mind-boggling simultaneous landing of the rocket’s two outer boosters.

— david z. morris, Fortune, "Watch a Moving New Falcon Heavy Launch Video from a Creator of Westworld," 11 Mar. 2018
The organizers encourage simultaneous marches to take place in local communities across the nation.

— emily wang, Teen Vogue, "Gucci Donated $500,000 to Help Parkland Survivors March for Our Lives," 23 Feb. 2018
Two simultaneous forces in the job market are driving this push toward lifelong learning.

— jeffrey selingo, The Atlantic, "The Third Education Revolution," 22 Mar. 2018
Earpieces that provide simultaneous translation to English are available to audience members.

— terry byrne, BostonGlobe.com, "Dead men do tell tales — in Russian," 21 Mar. 2018
The analysis also tracks a simultaneous rise in sensationalist Russian claims that the United States is itself pursuing offensive biological weapons.

— joby warrick, chicagotribune.com, "Poisoning of Russian ex-spy puts spotlight on Moscow's secret military labs," 18 Mar. 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.

Origin and Etymology of simultaneous

Latin simul at the same time + English -taneous (as in instantaneous) — more at same

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First Known Use: circa 1660

See Words from the same year

simultaneous Synonyms

Synonyms

coeval, coexistent, coexisting, coextensive, coincident, coincidental, concurrent, contemporaneous, contemporary, coterminous, synchronous;

Antonyms

asynchronous, noncontemporary, nonsimultaneous, nonsynchronous;

Synonym Discussion of 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.