KJVo virtually always means the King Jimmy is the only acceptable Biblical translation for Christians and completely without error. Some will say it's the only acceptable translation for English-speaking peoples and, in thise translations, it should mirror The Jimmy as much as possible...basically a distinction with little difference.
If there are other definitions, please feel free to provide them.
Aside: The reason cultists KJVoist are generally thought of as ignorant is not just because of their idolatrous views in this matter but the other views that so often coexist such as the extreme patriarchy, Trail of Blood, hyper-dispensationalism, anti-education, etc, blah blah crap that goes with it. (See also: Is Michelle Obama a man? )