British slang for a confused mess, muddle, or bungled situation; a complete failure or disorder.
Likely from 'ball up' (to confuse or tangle up), with 'ball' used as a verb meaning to form into a tangled mass, similar to 'balled up' or 'ballsed up.'
British slang has this wonderful tradition of using euphemistic versions of profanity—'ballup' and 'ballsed up' are polite ways of expressing frustration without actually swearing, yet they retain the punch of the original stronger terms.
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