When a stock's price suddenly changes direction, going against the overall trend, we call it a reversal. This can happen due to various factors, such as changes in market conditions or company performance. Reversals can be both positive and negative, and can offer opportunities to investors to make profits or cut losses. It is important for investors to keep an eye out for potential reversals and understand their implications. As a wise investor, always stay informed and analyze the market carefully before making any investment decisions.