Fattock
A fattock is a rotund, larger friend within a social group that always eats too much and often orders the most food when eating out etc.
Simon: Marc, why have you ordered SO much food... it's 10am?
Marc: *insubordinate yelping and denial*
Simon: You're such a fucking fattock.
Marc: *insubordinate yelping and denial*
Simon: You're such a fucking fattock.
Fattocks
The buttocks of a grossly obese individual. Most often a ghastly and unnerving sight to behold
Crikey me! Look at the fattocks on that Mc Donalds addict!