释义:任意的,随机的,不按照规定,规矩的,武断的,专政的。Based on random choice or personal whim, rather than any reason or system
Synonyms: capricious, random, chance

Something that’s arbitrary seems like it’s chosen at random instead of following a consistent rule. Team members would dislike their coach using a totally arbitrary method to pick starting players.

Even though arbitrary comes from a word meaning “judge” (arbiter), that doesn’t mean judges are always fair. Calling a decision-maker arbitrary is usually a negative thing, suggesting the person is making rules based on whim rather than justice. A coach who selects starting players arbitrarily isn’t strictly applying a rule; he could just be picking names out of a hat.

You’re too arbitrary, commander.

It’s too arbitrary. It’s unreasonable.

So you’re suggesting that the author just arbitrarily made fun of Sarah Jessica Parker for no reason.

Look at Planck’s constant. People say that’s arbitrary.