DELPHI (standing for "Detector with Lepton, Photon and Hadron Identification") was one of the four main detectors of the Large Electron–Positron Collider (LEP) at CERN, one of the largest particle accelerators ever made. Like the other three detectors, it recorded and analyzed the result of the collision between LEP's colliding particle beams.

Delphi ( or ; , ) is both an archaeological site and a modern town in Greece on the south-western spur of Mount Parnassus in the valley of Phocis. In myths dating to the classical period of Ancient Greece (510-323 BC), the site of Delphi was believed to be determined by Zeus when he sought to find the centre of his "Grandmother Earth" (Ge, Gaea, or Gaia). He sent two eagles flying from the eastern and western extremities, and the path of the eagles crossed over Delphi where the omphalos, or navel of Gaia was found.