Do you have a big head?
I don't mean is it bigger than average but are you big headed!
In other words, do you have a very high opinion of yourself because a big head does.
A man famous for his high self opinion was football manager, Brian Clough. (pronounced Klaf)So much so, that his nickname was old big head.
He was a very successful manager in the 70's and 80's but because of his outspoken manner, trouble often went hand in hand with success.
He was certainly quite a character and popular with the public. Here's part of a documentary about him.