Semileptonic is a term that is commonly used in the field of particle physics to describe certain types of nuclear reactions. The term refers to reactions in which a particle decays into another particle and a neutrino. Some synonyms for the word semileptonic include weak interaction, weak decay, and semiquantum. Another synonym that is often used in this context is beta decay, which refers specifically to the decay of a nucleus by emitting electrons or positrons. These terms are all related to the same concept of nuclear reactions that involve the weak interaction, and they are frequently used interchangeably in discussions of particle physics.