I just have to thank you for posting this thread! I too have been confused with the difference between these terms. As for "jumper"....When I've seen that word used, in my mind I picture a dress length sleeveless garment with a scooped neck. Usually worn with a blouse or light weight long sleeve pullover underneath. Now it makes sense if it's the UK term for sweater. I swear I learn something new here every single day!