APPLE INSIDER
Just as with the iPhone and iPad, macOS Big Sur includes a built-in way for you to avoid repetitive typing — and repetitive mistakes, too.
Text Replacement is in System Preferences, Keyboard, TextApple’s iPhone and iPad arguably need this feature more because, as good as their keyboards are, they’re on-screen ones and so harder to use than physical keys. However, if the technology is different, the need is the same.
Source: APPLE INSIDER