Adjusted Closing Price

What Does Adjusted Closing Price Mean?
A stock's closing price on any given day of trading that has been amended to include any distributions and corporate actions that occurred at any time prior to the next day's open. The adjusted closing price is often used when examining historical returns or performing a detailed analysis on historical returns.

Investopedia explains Adjusted Closing Price
The adjusted closing price is a useful tool when examining historical returns because it gives analysts an accurate representation of the firm's equity value beyond the simple market price. It accounts for all corporate actions such as stock splits, dividends/distributions and rights offerings.