Kappa, Phi, and Eta are all Greek letters that are used to represent honor societies. Kappa is the fifth letter of the Greek alphabet, Phi is the twentieth letter, and Eta is the eighth letter. These letters are often used to signify membership in an honor society, such as a college or university's chapter of the National Honor Society. The term 'Honor Society Letter' refers to the letters Kappa, Phi, and Eta, which are used to indicate membership in an honor society.