1. Someone that always exhibits an attitude of fun and excitement in what he/she is doing. This person often is the life of the party and invited to events just because friends/acquaintances know they will have more fun if he/she is there.
2. Person lacking of standard excuses for not having fun or going out, such as: "i'm tired", "I have to get up early", "I have my kid tonight", "My spouse said i can't go out", "I drank too much last night"
Bachelor: Can we go home now I have a wedding in the morning.
Best man: NO! You had better change your funitude right now or no more dances for you!
A combination of "Fat" and "Attitude"; the loud, boisterous, obnoxious arrogance often displayed by large and/or obese women. This is very common; many large women often try to overshadow their physical enormity with a similarly large and over-exaggerated large-and-in-charge attitude.
"Dude, that blubbery fat chick needs to shut up already. She's got a major case of fattitude."