Synonyms of simultaneous

simultaneous

adjective

ˌsī-məl-ˈtā-nē-əs 

as in concurrent

existing or occurring at the same period of time

a simultaneous release of the movie and its soundtrack on CD

Synonyms & Similar Words

• concurrent
• synchronous
• synchronic
• coincident
• coincidental
• contemporaneous
• contemporary
• coeval
• accompanying
• concomitant
• coextensive
• coterminous
• coetaneous
• coexistent
• incident
• coexisting
• attending
• attendant

Antonyms & Near Antonyms

• asynchronous
• nonsimultaneous
• nonsynchronous
• noncontemporary

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

Recent Examples of simultaneous

Prince continues to hold the all-time record for the most simultaneous wins on the Billboard 200. —Hugh McIntyre, Forbes.com, 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

Population growth at the wildland-urban boundary also increases exposure, while firefighting resources are strained as multiple regions face simultaneous emergencies. —Doyle Rice, USA Today, 31 May 2026

In simulations, ArrayLink supported up to four simultaneous spatial streams at distances of hundreds of kilometers, while maintaining two streams beyond 2,000 km (1,243 miles). —New Atlas, 30 May 2026