 Also used are "outperform", "neutral", "underperform", and "buy", "accumulate", "hold", "reduce", and "sell".If a stock is deemed underweight, the analyst is saying they consider the investor should reduce their holding, so that it should "weigh" less.For example, if an investor has 10% of their stocks in Retail, 25% in Manufacturing, 50% in Hi-Tech, and 15% in Defense, and the broker says that Retail is "underweight," then they are implying a smaller percentage of the stocks should be in Retail.