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

The danger for Europe’s competitiveness is that its economy could fall relatively further behind on both AI and energy prices, in the absence of accelerated, simultaneous investment into both sets of infrastructure. —Tasmin Lockwood, Fortune, 9 Sep. 2025

Trainers also staged simultaneous situations, such as protecting a lawmaker while confronting a suspicious man nearby who turned out to have a gun. —Beatrice Peterson, ABC News, 9 Sep. 2025

Sports broadcasts represent the one programming format that continues to draw the large simultaneous audiences that advertisers crave and cable and satellite distributors need. —Brian Steinberg, Variety, 8 Sep. 2025

The simultaneous invasions by Nazi Germany and the Soviet Union at the beginning of World War II in 1939 nearly led to the erasure of Poland, which went on to survive after the conflict as a Soviet satellite state until transitioning to democracy in 1989 and joining NATO a decade later. —Tom O'Connor, MSNBC Newsweek, 7 Sep. 2025