Initially, the question was about a specific word's first use in a movie.  Which in itself, while intriguing due to the subjet matter, is different from our other *first occurences* because asking about a *specific word* is getting to be a little *too* nit-picky as pointed out in the comments.

Secondly, part of it is from the fact that I had attempted to make it more general, using swearing in general, but as it turns out, there is actually an [exact duplicate](http://movies.stackexchange.com/questions/1786/era-of-profanity-in-movie-scripts) of another question. 

You need only look in the comments from @stevvve and @Flimzy.  

I will be merging the two shortly.