arbitrary

/ˈɑrbɪˌtrɛri/

based on or subject to individual discretion or preference or sometimes impulse or caprice

中文释义：任意的；武断的；专制的

The teacher's grading seemed arbitrary, with no clear criteria for high marks.

老师的评分似乎很随意，没有明确的高分标准。

An arbitrary decision by the manager led to confusion among the staff.

经理的武断决定导致了员工间的混乱。