Maligner and Zapper

Maligner noun - One who attacks the reputation of another by slander or libel.

Zapper and maligner are semantically related in critic topic. In some cases you can use "Zapper" instead a noun "Maligner", when it comes to topics like faultfinder.

Zapper noun - An electrical device that can injure or kill by means of electric currents.

Maligner and zapper are semantically related in critic topic. You can use "Maligner" instead a noun "Zapper", if it concerns topics such as faultfinder.