[Rick TYler]

RE: What it's called?

First of all, I call it "cool"!

Trebuchets were the ultimate development of the stationary flinging-arm military weapon, but by the 14th century they were being overtaken by early cannon. Since no one alive now speaks a 14th century dialect, we are unlikely to be using the proper name in 21st century English, especially since I doubt medieval siege engines used in probably dozens of different kingdoms, duchies, and counties were all called the same thing. I believe were are applying our modern passion for rigid definitions to devices created in a time where no such cladistic hegemony existed.