in a way that shows a complete lack of respect, as if something is stupid or of no value

"What would that accomplish?" she asked derisively. “那能完成什么？” 她嘲讽地问道。

Letters sent in the post are now derisively called "snail mail". 邮寄的信件现在被嘲笑地称为“蜗牛邮件”。