Prices for a particular instrument or sector might have strong support and continue to quickly rise, resulting in a temporary "bulge" in price. Bulges are characteristically fast moving and short-lived. Buying may continue until the security is overbought, and prices drop off, sometimes dramatically. Investors who jump on late, hoping that prices will continue to rise, often miss the move entirely due to its short-term nature.
Investment dictionary. Academic. 2012.