What do we call the amount of money gained from an investment?

The amount of money gained from an investment is most accurately referred to as profit. Profit represents the financial gain realized when the amount earned from the investment exceeds the costs associated with that investment. It reflects the overall success of making that investment, encompassing all revenues minus all expenses related to the investment.

While "Return on Investment" is a commonly used term that measures the efficiency of an investment and calculates the ratio of profit or loss relative to the investment cost, it doesn’t specifically represent the dollar amount gained. Capital Gain refers to the profit from the sale of an asset and is only relevant when a specific sale happens, while Equity Gain does not have a widely recognized definition in finance and is less commonly used. Thus, while these terms relate to the outcomes of investments, profit most succinctly encapsulates the total money gained, making it the correct choice in this context.