This component uses NHunspell for spell checking. NHunspell is a C# library that wraps native libraries for Hunspell and Hyphen. 
NHunspell's homepage: http://www.crawler-lib.net/nhunspell.

NHunspell can use Open Office dictionaries for spell checking. Open Office dictionaries are distributed as Open Office Extension (.OXT). 
In fact the Open Office extension files are Zip files. To get the dictionaries you must download and un-zip the .OXT file.

Open Office Dictionaries:
http://extensions.services.openoffice.org/dictionary

The spell checker Hunspell needs two files:
Dictionary file with .DIC extension  (e.g. en_US.dic)
Affix file with .AFF extension (e.g. en_US.aff)

Important: Dictionaries have a own license which may not be public domain. Check the dictionary license first before you use them! 
