1, The full form of FSI is Foreign Service Institute. It’s used on Governmental ,Departments & Agencies in United States

Foreign Service Institute (FSI) is the Federal Government’s primary training institution for officers and support personnel of the United States foreign affairs community, preparing American diplomats and other professionals to advance U.S. foreign affairs interests overseas and in Washington.

2, The full form of FSI is Fuel Stratified Injection. It’s used on Technology ,Automotive in Worldwide

Fuel Stratified Injection (FSI) is a proprietary direct fuel injection system developed and used by Volkswagen AG, as well as its luxury subsidiary Audi. In FSI technology, the fuel is injected directly into the combustion chamber and atomised into a fine spray. This can contribute to better use of the fuel and achieve higher performance and better dynamics than conventional engines.

3, The full form of FSI is Henry Post Army Airfield. It’s used on Transport & Travel ,Airport Codes in United States

Henry Post Army Airfield (IATA code: FSI, ICAO: KFSI, FAA LID: FSI) is a military use airport located at Fort Sill in Comanche County, Oklahoma, United States.

4, The full form of FSI is Floor Space Index. It’s used on Academic & Science ,Architecture & Constructions in India

Floor Space Index (FSI), also referred to as Floor Area Ratio (FAR), is the ratio ratio of total floor area of a building to the total lot area. Calculated by dividing the total square footage in the building by the square footage of land area. Municipalities and governments allow only a certain FSI. Otherwise very tall buildings in a narrow space would be constructed leading to parking and various other problems.