Protest

Latin protestari — to declare publicly. From pro- (before, publicly) + testari (to witness, testify). Originally a formal legal declaration — a public testament. The sense of opposition or objection came later.

The same event — people in streets challenging authority — is called a protest by sympathizers and a riot by opponents. Coverage studies consistently show the word choice tracks political alignment. The right to protest is constitutionally protected; the description of what counts as a protest is not.