Same word as piratical:

anarchic, anarchical, anarchistic, bad, barbarous, chaotic, contumacious, criminal, despotic, disobedient, disordered, disorderly, evil, fierce, heterodox, infringing, insubordinate, insurgent, mutinous, nihilistic, noncompliant, nonconformist, piratical, rebellious, recusant, revolutionary, riotous, savage, seditious, tempestuous, terrorizing, traitorous, turbulent, tyrannous, uncivilized, uncultivated, unorthodox, unpeaceful, unrestrained, unruly, untamed, violent, warlike, wild