Having sex with a customer after work with the intent of selling a contract for commission, then defecating in their sleeping quarters. Also, sometimes a right face slap using the bellend is included.
One time I flew out and boned this customer right after work - then I convinced her to buy an AA contract. Then I took a dump in her bed.
"I couldn't get over his Britishness"
"I dated her because of her Britishness"
"My family is full of Britishness"
"I have more Britishness in my body than anybody else"
When the overall country (Britain) is used to spread the dissapointment or a failure of an individual region (Scotland/Ireland/Wales/but normally England). When regions pick and choose their Britishness to suit them.
When Henman loses a tennis match, it's a sad day for "Britain", not "England", and when Murray wins a match, it's a good day for "Britain" not "Scotland". Perhaps I'm biased (being a scot) but it always seems that way. Selective Britishness! Hah!