Ksi
Ksi is an abbreviation that can refer to different concepts depending on context. In engineering and materials testing within the United States customary system, ksi stands for kilo-pounds per square inch. It is a unit of stress or strength equal to 1,000 pounds-force per square inch. One ksi equals about 6.895 megapascals. The term is commonly used to express the compressive strength of concrete, yield strengths of steel, and other materials, with values such as 4 ksi or 6 ksi indicating higher strength.
In popular culture, KSI is the stage name of Olajide Olatunji, a British YouTuber, rapper, and boxer.