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;
“Malcolmjust tried out a total load of bollocks on me; I told him straight, you’re talking through your arse.”
When you fail at something in life (eg. failing an exam or not getting a job), go home and spend an hour just standing in the shower, propping yourself up against the wall with your eyes on your feet.
Caleb knew the only thing to do after he didnt get prefect was take a failure shower.
And dying in yo' bed many years from now, would ya be willing ta trade all da days from dis here day ta dat fo' one chance, just one chance, ta come back here as young men an' tell our enemies dat dey may take our lives but dey will never take our freedom ... YUB NUB!