The Oxford Thesaurus An A-Z Dictionary of Synonyms - separationn.

1) rift, break, split, split-up, divorce, break-up, disunion, estrangement: Their separation, after forty years, was a surprise. 2) partition, division, split, schism, dividing line, dissociation, disassociation, severance: The United States constitution provides for the separation of church and state. 3) disintegration, shattering, break-up, fragmentation, dismemberment, taking or keeping apart, segregation, division, disjoining, disjunction, fission, scission, rupture, schism, splitting, split, fracturing, fracture, break: After a crash, investigators supervise the separation of the aeroplane into its tens of thousands of component parts.