Secession

an act or instance of seceding.

( often initial capital letter ) U.S. History . the withdrawal from the Union of 11 Southern states in the period 1860?61, which brought on the Civil War.

( usually initial capital letter ) Fine Arts . a style of art in Germany and Austria concurrent with and related to Art Nouveau.

noun

breakaway , breakup , defection , disaffiliation , dissension , disunion , division , exiting , parting , rift , rupture , schism , separation , splinter group , split