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2.
Fantastically fat.
Jena weighs 200kg, she's fatastic
by raffik August 01, 2008
 
1.
People (or animals) that are hilariously fat and are therefore extremely amusing.
Dr. Phil: Welcome our fatastic guest Abby. She weighs 650 pounds and was air lifted into our studio this morning.

Abby: Thank you Dr. Phil for having me on your show. I would like to give a shout out to my fatastic husband and fatastic family.
by Fatastic Abby July 30, 2006
 
3.
The buzz you get from taking diet pills. It almost makes being fat fun.
I was fatastic today the way I was zooming around the house cleaning, like a plus size tornado. I don't know if I lost any weight, but I feel so great I almost don't care.
by MadamexXx March 03, 2009