D defs.my
Entry 2 senses Webster, 1913

Secession

/(sē̇*sĕsh"ŭn)/ · Se·ces·sion · IPA /səˈsɛʃən/
01 n. The act of seceding; separation from fellowship or association with others, as in a religious or political organization; withdrawal.
  1. 1.
    The act of seceding; separation from fellowship or association with others, as in a religious or political organization; withdrawal.
  2. 2.
    The withdrawal of a State from the national Union.(U.S. Hist.)
Phrases & compounds
Secession Church — (in Scotland). See Seceder.