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 As reported, last April Fondazione Milano Cortina 2026 unveiled the Olympics and Paralympics torch via two simultaneous events at the Triennale Milano museum here and at Expo 2025 in Osaka, Japan. Martino Carrera, Footwear News, 15 July 2025 What really caught my attention was Silicon Valley's self-narrative, of course, was a place that was endlessly optimistic and yet there was a simultaneous subculture of people spending larger and larger sums to build bunkers and getaway plans. Frank Langfitt, NPR, 22 June 2025 Quantum models perform simultaneous evaluations of multiple pathways, rather than testing them sequentially. Sadhasivam Mohanadas, Forbes.com, 9 July 2025 The presence of an American stealth warship in Japan—a U.S. ally—comes after China's simultaneous deployment of two aircraft carriers last month on the eastern side of the first island chain, a U.S. defensive line comprising Japan, Taiwan and the Philippines in the western Pacific. Ryan Chan, MSNBC Newsweek, 8 July 2025 See All Example Sentences for simultaneous
Recent Examples of Synonyms for simultaneous
Adjective
  • The concurrent blazes killed 30 people and destroyed more than 16,200 buildings – compared to 85 and 18,800 for the Camp inferno, which wiped out the Northern California town of Paradise.
    Jorge L. Ortiz, USA Today, 22 July 2025
  • In Father of the Bride Part II, Annie (played by Kimberly Williams-Paisley) and her mom Nina (portrayed by Diane Keaton) also have concurrent pregnancies.
    Luke Chinman, People.com, 22 July 2025
Adjective
  • That’s highly synchronous, resulting in many, many animals making that migration simultaneously.
    Noël Fletcher, Forbes.com, 23 May 2025
  • The sheer number of DNA shifts that must have occurred in rapid succession to create this synchronous outcome also reflects the strong pressure horses were likely under to become fast and tireless.
    Lauren Leffer, Popular Science, 27 Mar. 2025
Adjective
  • 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
  • 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
Adjective
  • The timing of these changes were roughly coincident with clarification of Information Blocking rules and Epic’s introduction of its own competing product.
    Seth Joseph, Forbes, 26 Feb. 2024
  • Another suggestion is that there were two more or less coincident eruptions, one each in northern and southern hemispheres.
    Erik Klemetti, Discover Magazine, 26 July 2011

Browse Nearby Words

Cite this Entry

“Simultaneous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/simultaneous. Accessed 29 Jul. 2025.

More from Merriam-Webster on simultaneous

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!