The Greek letter before Kappa is IOTA, which is the ninth letter in the Greek alphabet. It is represented by the symbol ι and has a numerical value of 10. IOTA is derived from the Phoenician letter Yodh and is used in many languages, including Greek, Latin, and Cyrillic. In mathematics, it is used to represent the imaginary unit. In physics, it is used to denote the electric current. In chemistry, it is used to represent the isotope of an element.