Example: I am looking to see if "arg" is a special keyword in Lua. I go to the Lua reference manual at http://www.lua.org/manual/5.1/manual.html. I search for "arg". I find hundreds of occurrences of the word "argument(s)" or "vararg".

Any ideas? I know Firefox won't implement whole words as a core feature (something about cluttering up the ui... argh...), and I couldn't find a good addon that implemented this well.