Synonyms of synchronous

synchronous

adjective

ˈsiŋ-krə-nəs 

as in concurrent

existing or occurring at the same period of time

the synchronous arrival of a baby sister and loss of a beloved grandmother strongly affected the child

Synonyms & Similar Words

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

Antonyms & Near Antonyms

• asynchronous
• nonsynchronous
• nonsimultaneous
• noncontemporary

Synonym Chooser

How does the adjective synchronous differ from other similar words?

Some common synonyms of synchronous are coeval, coincident, contemporaneous, contemporary, and simultaneous. While all these words mean "existing or occurring at the same time," synchronous implies exact correspondence in time and especially in periodic intervals.

synchronous timepieces

When can coeval be used instead of synchronous?

The words coeval and synchronous are synonyms, but do differ in nuance. Specifically, coeval refers usually to periods, ages, eras, eons.

two stars thought to be coeval

In what contexts can coincident take the place of synchronous?

The meanings of coincident and synchronous largely overlap; 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 might contemporaneous be a better fit than synchronous?

In some situations, the words contemporaneous and synchronous are roughly equivalent. However, contemporaneous is more often applied to events than to people.

contemporaneous accounts of the kidnapping

When is it sensible to use contemporary instead of synchronous?

The synonyms contemporary and synchronous are sometimes interchangeable, but contemporary is likely to apply to people and what relates to them.

Abraham Lincoln was contemporary with Charles Darwin

Where would simultaneous be a reasonable alternative to synchronous?

Although the words simultaneous and synchronous have much in common, simultaneous implies correspondence in a moment of time.

the two shots were simultaneous

Example Sentences

Recent Examples of synchronous

This spring, the park, located just outside Gatlinburg, Tennessee, will unveil its Nighttime Firefly Experience, an immersive installation that reimagines the rare synchronous fireflies that appear each year in Great Smoky Mountains National Park. —Taryn White, Travel + Leisure, 16 Mar. 2026

Kairos can deliver up to 330 pounds (150 kilograms) of payload to sun-synchronous orbit, according to Space One. —Mike Wall, Space.com, 3 Mar. 2026

No synchronous online classes will be held. —Eryn Dion, The Providence Journal, 24 Feb. 2026

In 1979 and for the next 15 years, the world averaged 22 synchronous fire weather days a year for flames that stayed within large global regions, the study found. —ABC News, 18 Feb. 2026