The correct spelling for cochonet is not feminine (sorry).... therefore it is not spelled cochonette as in Ian's mathematical presentation. Perhaps a correction is justified?
I mentioned it to Ian. It's up to him.
Cochonnet is a masculine word in French. Le cochonnet but it has many other names, le bibi, le buchon (the cork), le petit (the little one), commonly known as the jack or the target ball in English, Many English speakers call it "the coche" while not technically correct, most people know what you are talking about and it works!
Ian has corrected the spelling.