From Longman Business Dictionaryrandom walkˌrandom ˈwalk noun [singular] STATISTICSFINANCE the idea that an amount, level etc changes without any pattern, so that it is not possible to say what future amounts etc will be. Some people think, for example, that prices on financial markets follow a random walk, and that it is impossible to calculate what prices will be in the future by looking at price movements in the pastSome recent research has shown persistent exceptions to the random walk model.