/ɑːrbɪtrəri/ – Adjective
Definition: Tùy ý, không căn cứ vào quy định cụ thể.
A more thorough explanation: based on random choice or subjective personal wishes, rather than any objective policy, reason or system; with no reason, aim, or objective etc
Example: A trial court abuses its discretion when it reaches a decision so arbitrary and unreasonable that it amounts to a clear error of law.