A protest is a formal declaration of objection. When there are big meetings of powerful countries and corporations, there are often protests staged in front of the meeting building, by people who think that what's happening inside is wrong.
Protest is both a noun and a verb. You've probably seen news about protests, because people all over the world organize them when they need to get a message across urgently. A protest doesn't have to be on the world scale, however. You might protest against eating frozen pizza for the third night in a row, and you've certainly seen a little kid protest against going to bed. When protest is political, it's also known as dissent.
