A term used to describe someone, who having left the protection of a group of their own accord, then wishes to return to the group, only to be be rejected (and ridiculed for their stupidity).
If you leave America to live in China, and then decide you don't like Chinese food, but America won't let you return to live there, you are, without doubt, a 'Dilligaf'
Bob: 'John wants to come with us to the Pub'
Bill: 'Hasn't John got a Man-Bag
bill: 'Then he can get royally Dilligaffed!'