This is slang from the UK although it is used in Australia as well and can be used in number ways:
1 To make a foolish statement;
2 To talk nonsense or rubbish;
3 To say something which is quite obviously false;
4 To exaggerate your abilities or knowledge of a subject;
5 To bluff or boast about something;
6 To be a self-aggrandising twat;
Malcolm just tried out a total load of bollocks on me; I told him straight, you’re talking through your arse.”
by AKACroatalin September 13, 2016
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