形容詞 peremptory:

1. offensively self-assured or given to exercising usually unwarranted power
   同義詞：autocratic, bossy, dominating, high-and-mighty, magisterial
2. not allowing contradiction or refusal
3. putting an end to all debate or action

1. The teacher spoke in a peremptory tone.
   老師以命令的口吻說話
2. His peremptory tone irritated everybody.
   他那專橫的口氣激怒了大家。
3. He made a peremptory order.
   他下達了一個必須服從的命令。

per.emp.to.ry

adj.（形容詞）
Putting an end to all debate or action:
斷然中止：停止所有的辯論或活動：
例句：
a peremptory decree.
中止政令

Not allowing contradiction or refusal; imperative:
不容許反駁或拒絕的；不可侵犯的：
例句：
The officer issued peremptory commands.
軍官發(fā)出了不容許辯駁的命令

Having the nature of or expressing a command; urgent:
強求或命令的；緊急的：有下命令的天性的；急切要求的：
例句：
The teacher spoke in a peremptory tone.
老師以命令的口吻說話

Offensively self-assured; dictatorial:
過度自信的；專制的：
例句：
a swaggering, peremptory manner.
狂妄自大、過于自信的舉止

來源：
Latin peremptôrius
拉丁語 peremptôrius
from peremptus [past participle of] perimere [to take away]
源自 peremptus [] perimere的過去分詞 [拿走]
per- [per-]
per- [前綴，表.遍及.]
emere [to obtain] * see em-
emere [獲得] *參見 em-

【引伸】
peremp.torily
adv.（副詞）
peremp.toriness
n.（名詞）