"Just Every Essential Part" a quote from Maurice Wilks the chairman of the Rover company at that time his alternative idea and not meant to be the definitive explanation of the name "JEEP".

Researching about the early period of the LandRover and its Jeep ancestry, including talking to and mailing people who were around at the time goes against the generally accepted idea that "General Purpose or G.P." became the word JEEP. It is much more likely that the car was actually named  after a cartoon character. (Or perhaps a combination of the two). Also Jeep had been a military term in the American army for many years previously.

Before the WWII Jeep was designed, Popeye cartoons had  a magical creature which could go anywhere and do anything. This creature was called Eugene the Jeep. You can check this for yourself by watching original Popeye cartoons. These cartoons were very popular with American GIs in WWII and it seems impossible that the Jeep character did not give its name to the trusted GI's go anywhere vehicle.
 

The first appearance of Eugene the Jeep was in 1933 "The Eighth Sea". Characters that joined Popeye on the screen included Hamburger Maven J. Wellington Wimpy, Swee'pea, Eugene the Jeep and Poopdeck Pappy.
 

Click on the graphics below to learn more about the Jeep