believe it or not, this one was made for Gerald R Ford
As a word, the word jumper has the disadvantage that a jumper is nothing to do with jumping; but then do we really want to draw attention to the connection between a sweater and sweating?
Luckily there are universal sorts of jumpers. A boring tool which works by hammering itself into something hard (rock, usually) is a jumper; then we have jumper leads or jumper cables to coax recalcitrant car engines into life:
a jumper can be a terrifyingly reduced form of sled:
photo by Michael Muir-Harmony CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=17252207
or it can be (in Ireland) a person who changes his religion; or it can be simply something which jumps:
photo by Revital Salomon
photo from the archive of Josef Reischig
Or, of course, to see a jumper all you really have to do is creep up behind someone and shout boo!
But that would, I think, be unkind. And possibly cheating.
Spot the Frippet: a jumper. The garment word comes from the French jupe, from the Arabic jubbah, a long cloth coat. The leaping about word is probably an imitation of the suddenness of the action.