Tight Monetary Policy

What Does Tight Monetary Policy Mean?
A course of action undertaken by the Federal Reserve to constrict spending in an economy that is seen to be growing too quickly, or to curb inflation when it is rising too fast. The Fed will "make money tight" by raising short-term interest rates (also known as the Fed funds, or discount rate), which increases the cost of borrowing and effectively reduces its attractiveness. 

Investopedia explains Tight Monetary Policy
The Fed can sell Treasuries on the open market in order to absorb some extra capital during a tight monetary policy. This effectively takes capital out of the open markets as the Fed takes in funds from the sale with the promise of paying the amount back with interest. The Fed will often look at tightening monetary policy during times of strong economic growth.