Jump, an active word, that has etymologists on their toes! Meaning that its origin is not completely agreed upon.
Some would have it that jump comes from dialects of southern France, to be picked up by English occupiers during the Hundred Years War.
While I do think this is an interesting theory, I also feel it fails to explain the presence of similar vocabulary in other languages, whose speakers were not part of that war, such as Old Dutch gumpen, Low German jumpen, Danish gumpe, Swedish gumpa and guppa and Icelandic goppa.
All of these suggest to me that a Germanic root is far more likely than the proposed Gallo-Romance one. Not only that, but Chaucer also used it in the form jombren, and although Chaucer lived during the Hundred Years War, the form he used does not resemble typical French forms from that period.
I favour the theory that has jump coming to us from Proto-Germanic *gemben, itself from the older source of Proto-Indo-European root *gwemb- – to spring, hop, jump