Petrol Definition & Meaning – Merriam-Webster

Etymology

borrowed from French pétrole “petroleum, any of various products distilled from petroleum,” going back to Old French petteroile, petrole “mineral oil, petroleum,” borrowed from Medieval Latin petroleum — more at petroleum

Note:
The use of the word in English is apparently owed to a cooperative endeavor by the British distilling and oil refining firm Carless, Capel and Leonard and the engineer Frederick Richard Simms, who had purchased the rights to Gottlieb Daimler’s gasoline-powered engine. Though an attempt to register petrol as a trademark was unsuccessful, Carless, Capel and Leonard continued to use it as a marketing name. Note that French pétrole (rather than essence de pétrole) is used for distilled petroleum products by Gustave Richard in Les nouveaux moteurs à gaz et à pétrole (Paris, 1892). The now usual French word essence for “gasoline” is shortened from essence de pétrole.