90s-00s Merseyside slang, loosely meaning a ridiculous idiot. Calling someone a โgoatโ or a โpia goatโ was a common insult used around certain parts of Merseyside. The addition of the word bladder adds further a layer of ridiculousness.
Whata piaaa goat, absolute goats bladder!
That juggalo Jake is a proper goats bladder!!
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