1) Be a union buster 2) Become a splinter group 3) Become an ex-member 4) Break 5) Break a union 6) Break away 7) Break away formally 8) Break off 9) Break up 10) Disaffiliate 11) Drop out 12) Emulate SC in 1860 13) Form a splinter group 14) Formally break away 15) Leave 16) Leave a federation 17) Leave a group 1) Breakaway 
• (v. i.) To withdraw from fellowship, communion, or association; to separate one`s self by a solemn act; to draw off; to retire; especially, to withdraw from a political or religious body.
Se'cede' intransitive verb [ imperfect & past participle Seceded ; present participle & verbal noun Seceding .] [ Latin secedere , secessum ; pref se- aside + cedere to go, move. See Cede .] To withd...
[v] - withdraw from an organization or communion
to formally break away from an alliance or federation, such as a political union.
[SAT terms] withdraw from an organization or polity