jumper vs leaper

jumper and leaper both are nouns.

Word	Noun	Adjective	Verb	Adverb
jumper	Yes	No	No	No
leaper	Yes	No	No	No

As nouns, leaper is a hyponym of jumper; that is, leaper is a word with a more specific, narrower meaning than jumper:

Other hyponyms of jumper include bounder, hopper, ski jumper.

jumper (noun)	leaper (noun)
(basketball) a player releases the basketball at the high point of a jump	someone who bounds or leaps (as in competition)
a sleeveless dress resembling an apron; worn over other clothing
a loose jacket or blouse worn by workmen
a small connector used to make temporary electrical connections
a coverall worn by children
a crocheted or knitted garment covering the upper part of the body
an athlete who competes at jumping
a person who jumps