Definitions for "Photoelectric effect"
the emission of electrons by certain metals when the appropriate wavelength of light is shined on them.
Emission of electrons from a metal when applying light with photon energy larger than the workfunction of the metal
Ejection of electrons from an atom or molecule that has absorbed a photon of sufficient energy. The photoelectric effect is the operating principle behind "electric eyes"; it is experimental evidence for particle-like behavior of electromagnetic radiation.