What is the Full Form of PSI ?

PSI – Pound per Square Inch

Pound per Square Inch is a unit of pressure resulting from a force of one pound-force applied to an area of one square inch.

1 psi = 1 lb. (pound) / (1 inch)²

or

1 psi – 6894.75729 pascals (SI unit of pressure)

PSI – Population Service International

Population Services International is a global health organization Headquartered in Washington, D.C., (US) and Amsterdam. The organization provides clinical services and life-saving drugs for major diseases like HIV, Malaria and child Survival.