語源は不明、またはグラフィック?ノベルのどうでもいい登場人物Mr Zilchから、あるいはどもり声を真似て作られた人名かもしれない、派生語源little person(小さな人)、zero(ゼロ)など。
The [Cadence] agency aims to have each album cover actually promote the record, on the theory that "the day of pretty, boffy, zoomy and zingy covers for the sake of zilch is no more." ["Billboard," Oct. 28, 1957]