Fetching details from the dictionary...

to laugh mockingly; to smile with contempt; to jeer; to sneer
彼の提案を上司が冷笑って一蹴した。
The boss sneered at his proposal and dismissed it outright.
失敗した者を冷笑うような人間にはなりたくない。
I do not want to become the kind of person who sneers at those who fail.
周囲に冷笑われても自分の信念を貫き通した。
Even though those around him sneered, he held firm to his convictions.