Resist
resist
One synonym would be "servitude." Another could be "thralldom."A related word (not actual slavery) is vassalage.
anti
hinder or oppose
INDICT, or ACCUSE
mutiny
contra
revolt, resist, oppose
The word abolitionist means a person that was against slavery. :)
ANTI MEANS AGAINST
The answer is "protest"...
There are only a few 6 letter words that means against. A couple of these words are oppose, versus, and contra.