Accumulation refers to the gradual building up of a package of shares without the price being driven up quickly. This is a term from technical analysis and describes a period that often precedes a sharp rise in the share price. During the accumulation period, there is usually a significant transaction volume. The opposite of accumulation is 'distribution', where shares are gradually sold off.

This term is specifically relevant in the context of market analyses, where the behavior of investors and the movements of stock prices are closely monitored to predict future trends.