Definition: The word "antiprophet" in the Bible refers to a prophet who was not appointed or commissioned by God, but instead spoke out against a king's leadership, leading to his downfall. The term originally meant someone who contradicted God's will and did so in defiance, which is why it's often used metaphorically for a person who opposes authority or truth. It's significant because the Jews believed in a just God who could punish disobedience by those who opposed His plans and purposes.