dəs, (ˌ)dis+ noun
1. : the act or process of disintegrating or state of being disintegrated
disintegration of personality
specifically : a change in the composition of an atomic nucleus whether occurring spontaneously (as in the ejection of particles from the nucleus in radioactivity) or as a result of bombardment by particles (as by neutrons or protons)
2. : the transformation of an elementary particle into others (as of a neutron into a proton and electron)