A market condition in which the prices of securities are falling, and widespread pessimism causes the negative sentiment to be self-sustaining. As investors anticipate losses in a bear market and selling continues, pessimism only grows. Although figures can vary, for many, a downturn of 20% or more in multiple broad market indexes, such as the Dow Jones Industrial Average (DJIA) or Standard & Poor's 500 Index (S&P 500), over at least a two-month period, is considered an entry into a bear market.






Taobiz explains Bear Market
A bear market should not be confused with a correction, which is a short-term trend that has a duration of less than two months. While corrections are often a great place for a value investor to find an entry point, bear markets rarely provide great entry points, as timing the bottom is very difficult to do. Fighting back can be extremely dangerous because it is quite difficult for an investor to make stellar gains during a bear market unless he or she is a short seller.