Adding a dictionary to Microsoft Word or Pages

I would like to know if it possible to add a dictionary to the Word for Mac or Pages applications, and if I can, need to know what file format they must be in. I'm from South Africa, and would like to add a dictionary of a local language, Afrikaans, so that I can conduct spell checks in either of these applications, preferably Word.

I have found dictionaries online, but they cannot be recognized (in text format) when I try to add a "Custom Disctionary".

I know that there is an Afrikaans dictionary available for the Microsoft Word for Windows, but would my Mac recognise that file format?

Thanks for the help, and ideas,

Mark