In his book, "Shinken-ko" (A Consideration of the Sacred Swords), Masahide TAKASAKI mentions in the chapter 'Kusanagi no Tsurugi' that 'kusa' has the meaning of 'kushi' (串) and 'ki' (奇) which refer to 'holy power' (霊威), and 'nagi' has the meaning of 'nada' which refers to 'serpent.'
高崎正秀は『神剣考』「草薙剣考」において、クサ串奇、で霊威ある意とし、ナギナダ蛇であるとした。