Caviler and Zapper

Caviler noun - A person given to harsh judgments and to finding faults.

Zapper and caviler are semantically related In some cases you can use "Zapper" instead a noun "Caviler".

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

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