Weak Longs

Weak longs tend to be traders, not investors. Short-term traders typically only own a stock long enough to capture a price gain. They are not interested in holding the stock as a long-term investment. 

Weak longs don't want to take a loss on their short-term investment. A weak long will typically set a tight stop-loss order that instructs his/her broker to sell an investment if it losses even a small amount of money.