A more thorough explanation:

Definition: To completely get rid of something or cancel it. It can also mean to reject someone from a group or jury without giving a reason.

• The judge perempted the evidence because it was obtained illegally.
• The lawyer used a peremptory challenge to remove a potential juror from the trial.

The first example shows how perempt can be used in a legal context to mean to quash or do away with something. The judge decided to perempt the evidence because it was obtained illegally, meaning that it was completely removed from the trial and could not be used as evidence. The second example shows how perempt can be used in a social context to mean to reject someone without giving a reason. The lawyer used a peremptory challenge to remove a potential juror from the trial, meaning that the juror was rejected without any explanation.