W: (v) disintegrate [Related to: disintegration] (break into parts or components or lose cohesion or unity) "The material disintegrated"; "the group disintegrated after the leader died"
S: (n) disintegration (a loss (or serious disruption) of organization in some system) "a disintegration of personality"
S: (n) decay, radioactive decay, disintegration (the spontaneous disintegration of a radioactive substance along with the emission of ionizing radiation)