A meson is a hadron made of one quark and one antiquark bound together by the strong force. Mesons are unstable in most cases, so they usually exist only briefly before decaying into other particles. Common examples include pions and kaons, which are important in particle-physics experiments because they help scientists study how matter behaves at very small scales.
In cyber security, meson matters mainly as a useful analogy. A meson is a composite object whose true identity comes from how its parts interact, not from one visible feature alone. Defenders face a similar problem when analyzing alerts: one log entry or one sensor reading rarely proves an attack. Good incident response combines multiple signals, such as endpoint data, network traffic, and user activity, before drawing conclusions. The term is also used in technical writing to remind analysts that complex systems can produce short-lived, misleading patterns that need careful verification.