1.Definition: not allowing contradiction or refusal

"Spoke in peremptory tones", "Peremptory commands"

2.Definition: offensively self-assured or given to exercising usually unwarranted power

"A swaggering peremptory manner"

Related Adjective(s):autocratic, bossy, dominating, magisterial

3.Definition: putting an end to all debate or action

"A peremptory decree"