1) To sell something (usually a stock) that one does not own, with the anticipation that the item's value will decline and they will be able to buy it back at a later date for a lesser price.
2) To deny someone credit that they deserve. This is generally something a person does to him/herself.
1)
I sold your sister short last year for $100, then bought her back this year for a can of Skoal and a junior bacon cheeseburger. Damn that rag has really started to circle the drain.
2)
You: "So you're not going to let me beat it up, are you?"
Girl: "Nope, sorry. Denied! But don't sell yourself short...3 inches isn't really that small. At least you've got my chihuahua beat...I think."
(sell short)
by Nick D September 8, 2005
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Not reaching one's full potential. The origin of the term is "short selling" a stock (i.e., betting against a company). The "short seller" essentially "borrows" stock from a company and agrees to pay back the company whatever the stock is worth at some point in the future. The purchaser sells the stock immediately, anticipating that the price will fall over the next few months. If the stock price actually falls, the purchaser will pay back the company less money than what the purchaser sold the stock for.
Jane: "I'm not good at science classes."
John: "I think your selling yourself short."

Jane: "Want to see a movie tonight?"
John: "Let's not sell ourselves short here. I heard Warren G is putting on a concert in Williamsburg."
by ZeekZeek November 13, 2009
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(FINANCE) borrowing securities for immediate sale, in anticipation of a sharp decline. Short selling requires strong nerves and excellent market timing; it also requires the ability to locate tranches of securities to borrow. If the short seller is correct, then she can buy back the securities at a much lower price, and lock in very high profits with very little initial investment.

Closely related to the concept of a short position. However, a short position includes buying put options (for example), while a long position could include short selling put options. So they are not exactly the same.

If a short sellers are wrong about the market, they are left hastily covering shorts, or buying the item they borrowed at a HIGHER price than they sold it for.
Jim Fisk was a master of the short squeeze; he appeared to cooperate with short selling until he was able to call in loans, forcing his counterparties to cover their shorts.
by Abu Yahya September 2, 2010
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a finance term for when you sell a stock when you do not actually have any shares because you think the stock will go down and give you a profit (Basically you are betting against a stock). However, in terms of relationships selling someone short means you will gain by getting rid of them.
ex 1: man that girl didn't put out after two dates I am gunna have to sell her short.

ex 2: Girl you flaked on me three times in three days I'm shorting you (selling you short)

ex 3: dude Benjamin is being a Dick lately, gunna have to short him (sell him short) for a few days.
by Shumongous October 13, 2014
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