In the U.S, a sleeveless dress (or sometimes a skirt with an attached bib front) worn over a blouse.

In the U.K., a knitted garment worn on the upper half of the body (as Iain said, what Americans call a sweater).

A great science fiction novel by Stephen Gould, about a 17 year old boy who finds he has the ability to teleport anywhere he's been, and then has to get through his life being chased by the NSA and dealing with memories of the abuse he suffered from his father.

In basketball parlance, this is short for jump shot.

American slang (especially among law enforcement and/or hospital staff) for a suicidal person.
That's where the name of the song (listed above) comes from:

"wish you would step off of that ledge, my friend,
you have capsized the ship of lies that you've been living in"

Third Eye Blind-Jumper

Dark Humor

A small, rectangular dingus, with innards made of conductive metal (like brass, aluminum, or copper). Used to connect two pins together on a circuit board. Often used to configure ISA cards IRQ, DMA Channel, etc. Also used on some motherboards to configure clock multiplier and bus speed. Amazingly useful, really, these dinguses. Most of them are black, but they can be found in nearly any color of the rainbow.

There's an interesting etymological path from "jumper" as a sweater to PopeFelix's electrical dingus. As near as I can make it out, it goes like this...

• A jumper is a sweater -- a colourful garment you put on top of something else.
• A thin wire (an electrical lead) coated with some colourful plastic insulation is a "jumpered lead", or (in short) a "jumper", because it's a wire which is wearing a sweater.
• During industrial PCB design (e.g. on a computer's circuit board), single wires added after printing are called "jumpers", because they really are jumpers.
• Optional wires you connect to configure some portion of your circuit board are such jumpers.
• The black plastic dingus is invented; it's a short inflexible lead, which lets you configure some portion of your circuit board, so it must be a jumper.

Which explains why a small black thingy is named after a colourful woolen article of clothing.

Jump"er (?), n.

1.

One who, or that which, jumps.

2.

A long drilling tool used by masons and quarrymen.

3.

A rude kind of sleigh; -- usually, a simple box on runners which are in one piece with the poles that form the thills. [U.S.] J. F. Cooper.

4. (Zoöl.)

The larva of the cheese fly. See Cheese fly, under Cheese.

5. (Eccl.)

A name applied in the 18th century to certain Calvinistic Methodists in Wales whose worship was characterized by violent convulsions.

6. (Horology)

spring to impel the star wheel, also a pawl to lock fast a wheel, in a repeating timepiece.

Baby jumper. See in the Vocabulary. --
Bounty jumper. See under Bounty.

 

© Webster 1913

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Jump"er, n. [See 1st Jump.]

A loose upper garment; as:

(a)

A sort of blouse worn by workmen over their ordinary dress to protect it.

(b)

A fur garment worn in Arctic journeys.

 

© Webster 1913

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Jump"er, n.

A thing that jumps; esp., any of various tools or other contrivances operating with a jumping motion; as, (Mining, Quarrying, etc.),

an instrument for boring holes in rocks by percussion without hammering, consisting of a bar of iron with a chisel-edged steel tip at one or both ends, operated by striking it against the rock, turning it slightly with each blow.

 

© Webster 1913