Definition of simultaneousnext

Synonym Chooser

How does the adjective simultaneous differ from other similar words?

Some common synonyms of simultaneous are coeval, coincident, contemporaneous, contemporary, and synchronous. While all these words mean "existing or occurring at the same time," simultaneous implies correspondence in a moment of time.

the two shots were simultaneous

When can coeval be used instead of simultaneous?

Although the words coeval and simultaneous have much in common, coeval refers usually to periods, ages, eras, eons.

two stars thought to be coeval

In what contexts can coincident take the place of simultaneous?

In some situations, the words coincident and simultaneous are roughly equivalent. However, 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

When is it sensible to use contemporaneous instead of simultaneous?

The words contemporaneous and simultaneous are synonyms, but do differ in nuance. Specifically, contemporaneous is more often applied to events than to people.

contemporaneous accounts of the kidnapping

Where would contemporary be a reasonable alternative to simultaneous?

The meanings of contemporary and simultaneous largely overlap; however, contemporary is likely to apply to people and what relates to them.

Abraham Lincoln was contemporary with Charles Darwin

When might synchronous be a better fit than simultaneous?

The synonyms synchronous and simultaneous are sometimes interchangeable, but synchronous implies exact correspondence in time and especially in periodic intervals.

synchronous timepieces

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of simultaneous The gigs are separate and simultaneous, and the work is not easy, especially when your day job requires more rest and more recovery than that of the average person. Sean Gentille, New York Times, 4 June 2026 Tubi's simultaneous streaming limits are somewhat irrelevant, since anyone can watch content with or without an account. Jordan Minor, PC Magazine, 1 June 2026 Israel is currently maintaining a simultaneous military presence in Gaza, Lebanon and Syria, in addition to fighting a war with Iran, which has stretched its robust military to the breaking point. Melanie Lidman, Los Angeles Times, 1 June 2026 After the simultaneous awarding of the Russian and Qatari World Cups, in 2010, a process that was riddled with vote-buying, FIFA updated its statutes to make sure that such a thing would never happen again. Sam Knight, New Yorker, 1 June 2026 See All Example Sentences for simultaneous
Recent Examples of Synonyms for simultaneous
Adjective
  • The Esports World Cup 2025, which was the event’s second year, reached 750 million viewers worldwide and generated 350 million hours watched, with peak concurrent viewership of nearly 8 million during the League of Legends at EWC ’25 tournament.
    Todd Spangler, Variety, 18 June 2026
  • In the month since her Netflix debut, viewers have dissected everything about the now 21-year-old Shirilla, who is currently serving two concurrent sentences of 15 years to life in prison—her first parole hearing is scheduled for September 2037.
    Savannah Walsh, Vanity Fair, 18 June 2026
Adjective
  • And every spring, thousands of people throw their names into a lottery for a chance to witness synchronous fireflies in the Smokies.
    USA TODAY Network, USA Today, 10 June 2026
  • Additional features include dual-cylinder synchronous jacking technology designed to improve climbing and tower-extension safety, along with an intelligent digital control system that monitors operations throughout the crane’s lifecycle.
    Kaif Shaikh, Interesting Engineering, 9 June 2026
Adjective
  • For his last runway collection, unveiled in September, Michele constructed a parallel universe of side-by-side shows separated by a wall that when lifted revealed twins in identical looks in synchronic stride.
    Colleen Barry, Fortune, 24 Nov. 2022
  • With a lockable synchronic-tilt mechanism and special Z-Shape design, the Kaiser 2 can accommodate a weight up to 180kg, quite a bit more than normal mechanisms on office chairs and the back can be reclined to an angle of 160 degrees which can be locked when not in rocking mode.
    Mark Sparrow, Forbes, 11 Oct. 2021
Adjective
  • Will start doing upgrades in volume in a few months, coincident with more FSD features being released.
    Jack Ewing, New York Times, 2 June 2026
  • Regional banks bounced a bit, still down a couple percent on the week, as Thursday’s flush lower amid a few separate but coincident credit hiccups exacerbated underlying unease with the opaque and possibly lax lending across private credit and among smaller commercial banks.
    Michael Santoli, CNBC, 17 Oct. 2025

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Cite this Entry

“Simultaneous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/simultaneous. Accessed 20 Jun. 2026.

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