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 sisters’ mother, Vesta Louis, told Politico this week that federal investigators raided both of their homes in simultaneous operations on March 23, confiscating their cellphones and other electronics. Emily Hallas, The Washington Examiner, 2 Apr. 2026 Its omnidirectional architecture, AERIX T-16, allows thrust to be vectorized independently of the drone’s body orientation, enabling simultaneous vertical lift, lateral translation, and rotational movement. Jijo Malayil, Interesting Engineering, 31 Mar. 2026 But scientists still haven’t fully evaluated the effects of simultaneous exposures to many of these chemicals over a long period of time. Emma Gometz, Scientific American, 31 Mar. 2026 The move gives him three simultaneous top 10 titles, part of a broader surge that places 14 of his songs on the chart. Russ Penuell, Billboard, 31 Mar. 2026 See All Example Sentences for simultaneous
Recent Examples of Synonyms for simultaneous
Adjective
  • The game, which allows for highly realistic simulations of manned (or Kerballed) missions to space (including lunar landings), has seen its second-highest number of concurrent Steam players ever, only beaten by its full launch way back in 2015.
    Alan Bradley, Space.com, 9 Apr. 2026
  • As the city of Granbury prepares to hold concurrent meetings that will decide the fate of a potential power plant for a data center development, tensions swirl between residents and city officials surrounding their transparency — and some are threatening legal action.
    Emily Holshouser, Fort Worth Star-Telegram, 7 Apr. 2026
Adjective
  • The van is powered by a 94-hp permanent synchronous electric motor.
    New Atlas, New Atlas, 30 Mar. 2026
  • Anakeesta in Gatlinburg, Tennessee, is launching a Nighttime Firefly Experience inspired by the Smoky Mountains’ rare synchronous fireflies.
    Taryn White, Travel + Leisure, 16 Mar. 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
  • 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
  • The coincident new Moon contributes no light pollution, making 2025 ideal for Orionid viewing.
    Big Think, Big Think, 13 Oct. 2025

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Cite this Entry

“Simultaneous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/simultaneous. Accessed 11 Apr. 2026.

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