To Add a User Defined Dictionary

Download the required user dictionary from http://extensions.services.openoffice.org/dictionary and extract the .aff and .dic files.
  1. Assign the full path of the .aff and .dic files to MS_SPELLING_CUSTOM_AFFIX_FILE and MS_SPELLING_CUSTOM_WORD_FILE configuration variable respectively.
  2. In the Spelling Category of Preferences dialog, set the Language setting to Custom.
  3. Optional: Restart any spelling operations in progress.