

You got a link to your source on that?
Merriam-webster says mousquet came from the Old Italian moschetto meaning a small artillery piece. It’s also a term for a male sparrow hawk. Which there was a traditio of naming weapons after animals.
https://www.merriam-webster.com/dictionary/musket
The Wikipedia page for musketeer says this:
The Musketeers of the Guard were a junior unit, initially of roughly company strength, of the military branch of the Royal Household. They were created in 1622 when Louis XIII furnished a company of light cavalry (the “carabiniers”, created by Louis’ father Henry IV) with muskets.
https://en.m.wikipedia.org/wiki/Musketeer
So the term Musketeer comes from the fact that they are armed with muskets. I cant find anything about a mousquet being a place on the belt to hold stuff.
Mine follows me around the apartment and gets underfoot, tripping me up.
Also he will chew up any paper or cardboard that he can get to.