Autocorrect replacing words added to dictionary

I have added words to my dictionary in Writer to stop spellcheck flagging them but autocorrect is still replacing certain words.

For example: “Hexian” becomes “Hexane”

How do I prevent it changing these added words automatically? I do not wish to have to disable autocorrect in its entirety.

Auto-correction and spellchecking are different things and auto-correction is based on patterns defined in replacement table Tools -> AutoCorrect -> AutoCorrect Options -> Tab: Replace (entries in dictionaries are not involved in auto-correction). So in fact the only explanation that Hexian to become Hexane would be, that there is an entry for that in the replacement table. To test: Disable option [x] Use replacement table in Tools -> AutoCorrect -> AutoCorrect Options -> Tab: Options or search for Hexian.

That’s excellent. I found it in the table and fixed it.

Thanks for your help.