A weak market can make investors jittery and cause concern for businesses. To describe a market that is not performing well, there are a number of synonyms that can be used. These include, but are not limited to, soft market, sluggish market, unstable market, declining market, bear market, lackluster market, and slow market. Each of these terms implies that the market is not strong or healthy, and may be experiencing a downturn, recession, or other economic challenges. When describing a weak market, it is important to be cautious about the language used to avoid causing unnecessary panic or alarm.