Looking for the definition of ROI? Find out what is the full meaning of ROI on usp-skrivany.eu! ' Return On Investment ' is one option -- get in to view more. Definition of return on investment (ROI): The earning power of assets of a company is lower than its cost-of-capital, then the company will be better off by. Return on investment (ROI) measures the gain or loss generated on an Also, it's important to note that the basic ROI calculation does not take time into.