British slang for testicles; also used as an exclamation meaning nonsense or an expression of annoyance.
From Old English 'balluc,' testicle, from Proto-Germanic 'baluz.' The plural form became standard for the vulgar slang term.
Interestingly, 'bollocks' comes from the same root as the word 'ball,' and you can see this connection in other languages—German 'Ball' (ball) shares the prehistoric origin with 'Balz' (testicles), showing how roundness got encoded in these words.
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