Whatever food product you get from Taco Bell
which may be called a gordita
is not really a gordita.
A true gordita starts with a ball of masa and is hand-patted into a diameter which is usually something less than the standard corn tortillas. The end result is an irregular circle, four inches or so in diameter, and somewhere around 1/4 to 3/8 of an inch thick. This little bit of unleavened bread is then quickly deep-fried, causing it to puff up, despite it's unleavened origin. The little fat bread is then fished out of the hot oil, sliced with a thin knife half-way through the circumference and stuffed with your choice of beans, lettuce, tomatoes, guacamole, and perhaps chicken or beef chunks. Served to you in a piece of waxed paper, it is a favorite of street vendors.
It does indeed mean "little fat one."