CP1 may refer to: * Am star, a class of chemically-peculiar stars * Chicago Pile-1, the World's first artificial nuclear reactor * Complex projective line , or Riemann sphere, in mathematics * Vektor CP1, a South African pistol * Warren CP-1, an experimental monoplane * CP1: an EEG electrode site according to the 10-20 system * Pasir Ris MRT station, MRT station code This disambiguation page lists articles associated with the same title formed as a letter-number combination. If an internal link led you here, you may wish to change the link to point directly to the intended article.