Someone who publicly opposes armed conflict in general, or particular conflict, and usually causes conflict in the process.
A derogatory term directed at the bigotry of certain “peace” groups attempting to force their views on society.
Sorry I was late to work today sergeant. Some peacenik group was blocking the gate and antagonizing the Soldiers. I would have liked to express a little of my own ‘free speech’ on them, but instead I just used the other entrance.