[ding_dong_daddy_from_dumas]

2.: to speak or write in a scornfully jeering manner

I suspect you pretended not to understand.

[joesbucks]

https://en.wikipedia.org/wiki/Sneer

But I see some sources do place your definition as #2. Dictionaries use ranking order to display the most common usage of the word.

And let’s not forget, most people remember Dick Cheney’s facial expression as being a sneer.