Close Position
The act of taking the opposite position of the current position thereby getting out of a position in a particular stock or security.
Also referred to as "Closing Transaction."
Taobiz explains Close Position
If a broker recommends that you close your long position on a stock they mean "sell it immediately." For example if you have a short position in a stock for you to close the position you will need to take a long position, or in other words you have to buy back the stock.