LibreOffice collects words that you frequently use in the current session. When you later type the first three letters of a collected word, LibreOffice automatically completes the word.
If there is more than one word in the AutoCorrect memory that matches the three letters that you type, press CommandCtrl+Tab to cycle through the available words. To cycle in the opposite direction, press CommandCtrl+Shift+Tab.
To Accept/Reject a Word Completion
By default, you accept the word completion by pressing the Enter key.
To reject the word completion, continue typing with any other key.
To Switch off the Word Completion
Clear Enable word completion.