Im sticking with my initial guess and guessing they rederred to the jian as a tai chi sword at some point. Im adding to my guess that OP may have been drunk when he watched the movie and posted this. Again, without seeing the movie
Anyone who sees a film with subtitles and can speak/read both languages has had fun with the differences, even when they are done well. Sometimes, a concept just doesn't translate well, leading to "bad" subtitles. Other times, it seems clear the person doing the subtitles isn't actual fluent in one or the other of the languages.I often find english subtitles for Chinese rather amusing. Look at the link I provided and go through the weapons they are talking about and see which one they are referring to. But, as previously stated by @kempodiscipe, my money would be on the Jian, it is used in Taijiquan (Tai Chi Chuan), but not exclusively.
I attached a link to the picture of the part of the movie where this sword is used.
It looks like a sword with feathers. Maybe someone who reads Chinese can tell me what it says in the picture.