I was under the impression that a floppy disk is referring to the substrate that holds the data, not the cartridge that contains it. So a 3.5" floppy disk would be "floppy" in contrast to a 3.5" hard disk drive that has rigid metal or glass platters.
This nomenclature could be a regional thing though (I'm from the US).
This nomenclature could be a regional thing though (I'm from the US).