Synonyms for Disintegration (same or very similar meaning)
WordNet sense 1 (in a decomposed state):
decomposition
WordNet sense 2 (separation into component parts):
dissolution
WordNet sense 3 (the spontaneous disintegration of a radioactive substance along with the emission of ionizing radiation):
decay, radioactive decay
WordNet sense 4 (total destruction):
annihilation
From the ODE community, based on WordNet
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