It's rather straightforward, you have a "c2dictionary" key which is just for c2 to check that it's supposed to be a JSON for a dictionary object, and a "data" key which holds the list of key/value pairs.
Now if you have to do it by hand, it's still easier to build such list using a text editor than to create all the "add key" action in construct.
Now to use such thing, you just have to put that in a file, import it in the file folder of your project tree (in the project panel)
And then using the AJAX plugin, you request the file, and "on request completed" you load the AJAX.LastData value into a dictionary object.
With this, I could just add the words manually in that format? Sounds awesome.