“Asynchronous” vs. “Synchronous”: Time To Learn The Difference

Instead of going back into the classroom during the 2020 COVID-19 pandemic, many students transitioned to virtual learning—but this doesn’t mean that all of their classes were held live over video.

Some students were able to start the day on their own terms and work through assignments at their own speed. Does this mean their teachers were participating in asynchronous learning, or were these students doing synchronous work from the safety of their own homes? Let’s take a closer look.

What does asynchronous mean?

Asynchronous is an adjective that means “not occurring at the same time.” In digital technology, it refers to “having each operation started only after the preceding operation is completed.” Though different, these two definitions refer to things that occur at different times.

In 2020, asynchronous has seen a lot of use related to virtual learning environments. For parents who may be confused about its meaning, asynchronous here refers to learning methods that let students work at their own pace. Instead of the rigid constraints of a traditional classroom, kids participating in asynchronous learning can move through assignments at their own speed and are often aided by online discussion boards and emails. In an asynchronous course, a student does not need to meet in real time with a live class or teacher.

For example:

  • The teacher offered the students prerecorded videos and asynchronous assignments, which they were asked to complete on their own.
  • When coming up with lesson plans for the 2020 remote school year, Mr. Washington embraced asynchronous learning to help his students thrive.

How else would you use this word?

  • The online discussion board allowed the conference participants to conduct asynchronous conversations after attending their sessions.
  • When the team began working from home exclusively, employees relied on asynchronous methods, like email and other project management tools, to communicate.

The first recorded use of asynchronous was in 1740–50, and it combines the Greek-based prefix a-, meaning “without, not,” to synchronous, “occurring at the same time.” Synonyms for asynchronous include nonsynchronous and allochronic.

What does synchronous mean?

As noted above, asynchronous is a combination of the word synchronous and the prefix a-Synchronous is an adjective that’s defined as “occurring at the same time; coinciding in time; contemporaneous; simultaneous.” It means the opposite of asynchronous.

The first recorded use of synchronous was in 1660–70, and it originates from Late Latin synchronus via Greek sýnchronos. Synonyms for synchronous include coincident, contemporaneous, simultaneous, and synchronized.

Here’s one example of how you might use this word: after the car accident, surgeons decided to operate synchronously, with one repairing her leg while the other fixed her liver. In reference to virtual learning, synchronous learning occurs in real time instead of at a student’s pace and at their choice. This can occur in a traditional classroom setting or virtually.

For example:

  • Since Camila’s school was participating in synchronous learning, she had to log on dressed in her school uniform, ready to start her day at the exact same time as the rest of her class.

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How to use each word

Asynchronous and synchronous are antonyms as they mean the complete opposite of each other. Both words utilize the Greek syn-, meaning “together,” while asynchronous has the prefix a-, meaning “not.”

So keep in mind that when referring to something that happens at the same time, it’s synchronous, but for anything that doesn’t occur at the same time and is instead staggered or delayed, it’s asynchronous.

For example, in communication, speaking in person and video chats are considered synchronous, while email, texts, or chats are an asynchronous way to talk.

Other ways to use these words include:

  • They planned the trip so both would be flying synchronously and land at the airport around the same time.
  • Some online classes include a combination of both synchronous and asynchronous learning depending on what teachers and families are most comfortable with.
  • Although he had to pass a certain number of tests to become certified, he couldn’t take them synchronously and instead had to pass one at a time before he could take the next.


Virtual or not, the school year is brimming with information for everyone to learn, such as these common school acronyms. And since a lot of communication is bound to be asynchronous, it will probably helpful to figure out the best ways to incorporate emoji into the school day.


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