Hollywood is in love with the "F" word. I do not think it would be in conversational use in a convent no matter how screwed up the nuns were. In addition, the word was not invented until the 1400s and this movie was set in the 1300s.
shareHard to believe there wasn't a word for it before 1400. How'd we all get here then?
shareI would imagine he is only speaking about that specific word. Other words would have indicated the same thing.
IRRC, and I could be wrong, the "f" word was actually a polite and socially acceptable word for sexual activity when it was first emerged. Like many such words, it became an "obscene" term.