Rally

A rally is a significant short-term recovery in the price of a stock or commodity, or of a market in general, after a period of decline or sluggishness.

Stocks that make a particularly strong recovery in a particular sector or in the market as a whole are often said to be leading the rally, a reference to the term's origins in combat, where an officer would lead his rallying troops back into battle. While a rally may signal the beginning of a bull market, it doesn't necessarily do so.