SadakoMoose said:
About how offensive is the word pillock considered to be?
It basically means idiot or moron. We use it a lot in banter here in Britain. Like if somebody turns his friends DVDs and games into a hilarious set of dominos by falling against a shelf with them on you say it while laughing at him.
E.g. if I want to let someone know they've been really stupid I'll say:
'You bloody idiot, don't step there! That's broken glass and you're barefoot!'
If you want to be lighthearted:
'I found out the problem with the internet, I forgot to plug it in.'
'You pillock, just because it says WIRELESS doesn't mean you don't need to plug it into the mains.'
I normally say bloody to let someone know how dangerously stupid (like high voltage style) they're being.