Antibunching is a term that refers to the phenomenon where photons do not bunch together but rather exhibit an anti-correlation behavior. This is important in the field of quantum optics, where it is necessary to use single photons for various applications. Synonyms for antibunching include photon correlation, non-coalescence, and photon anti-bunching. Photon correlation refers to the measurement of the correlation between two or more photons, which is often used to study the properties of light. Non-coalescence refers to the fact that photons do not merge but rather remain separate, while photon anti-bunching refers to the fact that photons tend to avoid grouping together in space and time.