A negative muon is a subatomic particle that has a negative electrical charge. It is also known as a negatively charged muon or muon-. This particle is similar to an electron in many ways, but it is much more massive. Scientists use the negative muon to study properties of materials and to better understand the behavior of particles in the universe. There are a few other terms that can be used as synonyms for negative muon, including muon decay, muon minus, or antimuon. Each of these terms describes a different aspect of the negative muon, but they all refer to the same subatomic particle.