This is just a note for myself. And I'm still a learner of vim, but I did a tiny progress today.
As I have physical disability at my hand, word completion is a feature good to have.
Here is what I did today.
1. Add the following line to ~/.vimrc
isamu@hope:~$ grep dict .vimrc
2. Get word_complete.vim from :
edit the file for uncomment "min_len" and "accept_key" probably at line 57, 58
and put the file into ~/.vim/plugin, which is the default vim plugin directory.
3. At ex mode of vim, type ":call DoWordComplete()" starts word completion,
Or at [insert-mode], [C-x][C-k] does the same job.
Pitfall: Without step 1, step 2 doesn't work. Vim needs a dictionary, of course.