How do I use an Ispell dictionary with Postgres text search? Postgres can use Ispell-compatible dictionaries in text search, but does not provide the required files.
This example uses the Canadian English dictionary, but you can try it with others as well. 

These are the steps needed for Windows:


Open http://src.chromium.org/svn/trunk/deps/third_party/hunspell_dictionaries/en_CA.dic 
Select all of the text, copy it, and paste it to Text Mechanic: http://textmechanic.co/Sort-Text-Lines.html. Add a line break at the end. 
Open http://src.chromium.org/svn/trunk/deps/third_party/hunspell_dictionaries/en_CA.dic_delta
Select all of the text, copy it, and paste it below the previously pasted text in Text Mechanic.
Scroll to the top, and select and cut the first line (should be a five digit number), and get rid of the line break.
Click the Alphabetical button, and wait for the text to sort.
Select all of the text and copy it to the clipboard
Open Windows Notepad as an administrator
Paste the text from Step 7 into Notepad
Save the file as en_ca.dict (with UTF-8 encoding) to your Postgres text search folder. Mine is C:\Program Files\PostgreSQL\9.3\share\tsearch_data .
Open http://src.chromium.org/svn/trunk/deps/third_party/hunspell_dictionaries/en_CA.aff , select all, copy, and paste to Notepad. Save the file as en_ca.affix to your Postgres text search folder.


In PgAdmin, run the following SQL:

create text search dictionary ispell_en_ca (
  template  =   ispell,
  dictfile  =   en_ca,
  afffile   =   en_ca,
  stopwords =   english
);

--make sure it works:
select * from ts_lexize('ispell_en_ca', 'colours');

/* 
result:
ts_lexize
text[]
{coloured,colour}
*/


You will need to create a new text search configuration to use the dictionary.