There are several synonyms for the term "closed end investment companies", which refer to investment companies that have a fixed number of shares and a fixed duration of operation. These terms include closed end funds, closed end mutual funds, and exchange traded funds (ETFs). While these terms may refer to different types of investment companies, they all share the feature of a limited number of shares and a fixed investment period. Closed end investment companies are often compared to open end investment companies, which allow for the creation and redemption of shares on a continuous basis. Closed end investment companies offer investors the potential for capital appreciation and income, with the benefit of diversification and professional management.