Conduct or language inciting rebellion against the authority of a state.
Insurrection; rebellion.
[Middle English sedicioun, violent party strife, from Old French sedition, from Latin sēditiō, sēditiōn- : sēd-, sē-, apart; see s(w)e- in Indo-European roots + itiō, act of going (from itus, past participle of īre, to go; see ei- in Indo-European roots).] se·di'tion·ist n.