One of the mysteries of the English language finally explained.
Of, designating, or involving a substance designed to be poured on to or over something, especially a parasiticide or insecticide designed to be poured on to an animal's body.
A pour-on substance, especially a parasiticide or insecticide.
1960s; earliest use found in Journal of Economic Entomology. From to pour on.
In this article we explore how to impress employers with a spot-on CV.