1. Used to describe someone who is (slightly) chubby, and as become so over the christmas/summer holiday period.
2. Or, someone who morbidly obese and you don't want to hurt their feelings, yet you stil want to bring them to the attention of their weight gain.
1. 'oh mighty me darling, you seemed to have gained ten pounds over the christmas period! Time for the old detox!'

2. 'S**t! Look at that big moma, shes ever bigger than yours!'
'Mate, shut it, be nice to her, shes my aunt'

'alright sorry, shes festively plump'

'thats better'
by Valentina Osborn July 13, 2006
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The response when someone calls you fat...
Dude 1: Daym girl...why are you so fat?
Dude 2: I'm not fat, I'm festively plump
by thegirlthatkrumps December 22, 2010
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