At present, the word Jeep stands for an American car brand that specializes in SUVs, crossovers, and other off-road vehicles. But during WW2, and for many years later it was a generic name for any light-military 4×4 drive vehicle.
According to most researchers ‘Jeep’ is an abbreviation of G.P, which stands for ‘General Purpose’ (vehicle). This abbreviation was probably influenced by ‘Eugene the Jeep’ a then famous cartoon from the Popeye comic strip who could only say Jeep.
So, how did the military term “immigrated” to civilian vocabulary? – in 1941, Irving “Red” Hausmann – the Willys-Overland Motors test driver – was invited to demonstrate the new vehicle’s off-road capability by driving it up the steps of the United States Capitol. When asked by the Washington Daily News columnist, Katharine Hillyer, “What is it?”, Hausmann, that a few days before heard soldiers calling it a Jeep, answered, “It’s a jeep.”
Bonus Fact 1: The word ‘Jeep’ was used as early as World War I as US Army slang for new uninitiated recruits, or by mechanics to refer to new unproven vehicles.
Bonus Fact 2:The US Army modern light light military 4×4 vehicle, the Humvee, stands for High Mobility Multipurpose Wheeled Vehicle. Namely, it should have been pronounced as HMMWV, Humvee is its colloquial name, and the letter U was added to make it easier to pronounce.