(vulgar, slang, derogatory) A round, overweight, or obese person.
toki’s tourist guide vision is such a fatass. She weighs 600 pounds
NOT TO BE CONFUSED WITH 'fat ass'.
1 - Fatass = someone or something that is fat.
2 - Fat ass = a big ass.
1: Dude, my cat is such a fatass!
2: Damn, she got a fat ass!