People who make unkind smiles to show they do not respect someone or something.
Sneerers are not nice people because they make others feel bad with their unkind smiles.
Examples:
The sneerers laughed at her when she fell down.
I don't like to be around sneerers because they always make fun of others.
The sneerers in the class made fun of the new student.
The sneerers thought they were better than everyone else.
The sneerers always look down on people and make them feel small.
The sneerers in the movie were not nice at all.