A person of extreme dietary (and perhaps spiritual) discipline who eats only the reproductive offshoots of plants. This includes not only apples and oranges but nuts, grains, melons, tomatoes, eggplants, cucumbers, etc. A pizza marinara (no cheese, no meat) is a fruitarian meal, and so is a peanut butter and jelly sandwich.
Fruitarianism is closely related to veganism which itself is a subset of vegetarianism and is widely popular in the non-Western world. Unfortunately, as with anyone who practices extreme discipline, the fruitarian is often hated and ridiculed by fatasses who lack a level of dedication. Famous fruitarians: Gandhi & Steve Jobs (founder of "Apple" computers--hence the name).
I used to know a dude who was a total porkrind munching fatass, but he could never get a date because he smelled so bad, and he eventually died of a heart attack at age 47. He should've gone fruitarian.