reactionary (adj.) Look up reactionary at
1831, on model of French réactionnaire (19c.), from réaction (see reaction). In Marxist use, "tending toward reversing existing tendencies," opposed to revolutionary and used opprobriously in reference to opponents of communism, by 1858. As a noun, "person considered reactionary," especially in politics, one who seeks to check or undo political action, by 1855.