The parking space at the end of a fast food restaurant drive-thru that an employee sends you to after you order so much food that they can't serve it to you without holding up the line of cars behind you.

As a verb it is the act of getting sent to the Fatty Square.
As a noun

Friend 1: I got sent to the fatty square after my colossal order brought the drive-thru to a screeching halt.

Friend 2: You are fat and have an eating disorder

As a verb

Patron: Can I have 3 hard tacos, 1 with no lettuce; 5 soft tacos, two supreme; three chalupas, two baja style, one supreme; 3 pintos & cheese, no red sauce on one of them; one taco salad; and 4 gorditas?

Cashier: That will be $29

Patron: Here you go.

Cashier: Please pull ahead and we will bring it out to you.

Patron: Oh no! I 've been fatty squared!
by mildmanneredclarkkent July 17, 2009
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