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

Now researchers in China have a new way to dramatically scale up the bandwidth of quantum networks by increasing the number of simultaneous quantum communication channels. — IEEE Spectrum, 2 Sep. 2026

The average age for simultaneous child and elder care is now 34, not Gen X, with 80% experiencing a sudden onset. — Jasmine Browley, Forbes.com, 30 Aug. 2026

Her work’s recognition by international curators and her decision to start drawing again were more or less simultaneous events. — Laura Preston, New Yorker, 30 Aug. 2026

The simultaneous de-rating of ASML and re-rating of peers largely explains the stock's significant underperformance over the past 12 months. — Michael Bloom, CNBC, 29 Aug. 2026