summing up an abbreviation is a shortening of a word or a phrase an acronym is an abbreviation that forms a word an initialism is an abbreviation that uses the first letter of each word in the phrase thus some but not all initialisms are acronyms
ROI, or return on investment, is a common business term used to identify past and potential financial returns. Managers and executives look to the ROI of a project or endeavor because this indicates how successful a venture will be.
ROI means Return On Investment, and is a measure of how effective a business cycle is in turning one dollar into two. If you invest 1 million to gain 50k, you might consider pulling your capital out of that cycle, in favor of a model with a larger ROI. Capital in this case includes assets, such as property.