2. 1. Interest eared on the principal and may be for a number of years may be called is the process of accumulating interest in an investment over time to earn more interest. 3. The interest earned on both the initial principal and the interest reinvested from prior periods is referred to as 2. 1. Interest eared on the principal and may be for a number of years may be called is the process of accumulating interest in an investment over time to earn more interest. 3. The interest earned on both the initial principal and the interest reinvested from prior periods is referred to as