| disrupter(noun, advocate, radical, partisan, reactionary) |
| dissentient(adjective, liberalism, factional, freethinking, progressiveness) |
| dissident(noun, adjective, radical, partisan, reactionary) |
| dogmatist(noun, advocate, radical, partisan, reactionary) |
| emendatory |
| extremist |
| fellow traveler |
| fighter(noun, radical, partisan, reactionary, leftist) |
| firebrand(noun, radical, partisan, reactionary, leftist) |
| fomenter(noun, advocate, radical, partisan, reactionary) |
| gradualistic |
| incendiary(noun, radical, partisan, reactionary, leftist) |
| inciter(noun, advocate, radical, partisan, reactionary) |
| instigator(noun, radical, partisan, reactionary, leftist) |
| left-winger(noun, dissentient, liberalism, progressiveness) |
| leftist(noun, advocate, radical, partisan, dissentient) |
| malcontent(noun, radical, partisan, reactionary, leftist) |
| meliorist |
| melioristic |
| mover(noun, advocate, radical, partisan, reactionary) |