adjective

1. Law
   1. barring further action, debate, question, etc.; final; absolute; decisive
   2. not requiring that any cause be shown a peremptory challenge of a juror
2. that cannot be denied, changed, delayed, opposed, etc., as a command
3. intolerantly positive or assured; imperious a peremptory manner

Etymology: LL peremptorius, decisive, final < L, destructive, deadly < peremptus, pp. of perimere, to destroy < per-, intens. + emere, to take, buy: see redeem