means A jumper is one who or that which jumps — whether a sweater pulled over the head, a person who leaps, a daredevil diving from heights, or a short wire connecting two points in a circuit.

from From the verb 'jump,' itself a word of uncertain origin that surfaced in the 16th century, possibly imitative — the sound of a sudden bound. The garment 'jumper,' though, likely came by a different road: probably from 'jump' or 'jumpe,' an old word for a short loose coat or jacket, which may trace back through dialect to the French 'jupe' (a skirt or tunic), itself borrowed from Arabic 'jubba,' a long garment. So the sweater you tug on and the cliff-diver who tugs at fate may share only a spelling, not a single ancestor — two lives that grew into one word.