The name "petroleum jelly" is based on its historical derivation from petroleum, which was the original source of the jelly-like substance. When first discovered in the 19th century, people noticed the jelly-like material forming on oil rigs and realized its potential for various applications. Since the substance was obtained from petroleum, it was aptly named "petroleum jelly."

Over time, it was found that petroleum jelly could also be produced using purified mineral oils rather than directly from crude petroleum. However, the name "petroleum jelly" persisted even though the primary ingredient was no longer derived solely from petroleum but from highly refined mineral oils. This is because the term "petroleum jelly" had become widely recognized and associated with the product's properties and uses.

Additionally, the term "oil" is often used in reference to liquid substances, while petroleum jelly is a semi-solid, viscous material. Using "jelly" in the name accurately describes its physical form.

Therefore, the name "petroleum jelly" remains as a conventional and commonly recognized term for this product, even though its contemporary production may not always involve direct use of petroleum as the primary source material.