peremptory puh-REMP-tuh-ree, adjective:

1. Precluding or putting an end to all debate or action.
2. Not allowing contradiction or refusal; absolute; decisive; conclusive; final.
3. Expressive of urgency or command.
4. Offensively self-assured or given to exercising usually unwarranted power; dictatorial; dogmatic.

Peremptory comes from Latin peremptorius, “destructive,” from peremptus, past participle of perimere, “to take thoroughly, to do away with, to destroy; hence, to thwart, to frustrate,” from per-, “thoroughly” + emere, “to take, to obtain.”