What is Futtocks?
1.
Disproportionately large and heavy buttocks.
Look at the futtocks on Russell. They make his head look really tiny.
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2.
1) Any part of the body you are referring to.
2) A lazy or silly person whom you wish to motivate into action
3) A coarse expression of annoyance
1) Get off your futtocks!
2) Shut up ya futtock (best said with a northern accent)
3) 'Oh futtocks!'
See