Asynchronous is an adjective that means not existing or happening at the same time.

The Greek word Chronos (CROW noss) refers to ‘time.’ Synchronous events occur at the same time. If we add an A as a prefix to this, we get the opposite — things not occurring at the same time. Here’s an example:

As a kid, I’d always imaged cave men playing with pet dinosaurs. It wasn’t until later that I learned that the existence of dinosaurs and early man were asynchronous events.