First, there is no need to modify the built-in dictionary, as the facility exists to populate your own custom dictionary, which is then used alongside the provided one.
Actually, adding words to the custom dictionary individually is perhaps not as complicated as it sounds. Just paste the word list into a new (empty) document, where all the words will be underlined as wrongly spelled. Then run the spelling checker and simply click Add repeatedly. But that may be tedious for five hundred entries in one go.
The default custom dictionary is standard.dic, which is a plain text file to which you may well be able to add your new word list directly, by opening it in a plain text editor (perhaps Notepad). You will find this in the "wordbook" folder inside your LibreOffice user profile. Where the profile is depends on your operating system. You appear to be using Windows, in which case the profile is likely to be
C:\Documents and Settings\<user name>\Application Data\libreoffice\4\user
or
C:\Users\<user name>\AppData\Roaming\libreoffice\4\user
- depending on the Windows version - where <user name> is the name you use to log on to Windows.
More easily, you can access it at
%appdata%\libreoffice\4\user
Once you have modified standard.dic (with LibreOffice closed, of course), you can start LibreOffice and go to Tools | Options... | Language Settings | Writing Aids | User-defined dictionaries | standard [All] | Edit... to check the result.
I trust this helps.
Brian Barker
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