A big wheel may be the head of a company, a political leader, a famous movie star.

VOA: special.2009.11.29

He has a "big head." A person who is filled with his own importance and pride is said to have "his nose in the air.

VOA: special.2009.03.08

And every night, late at night, I turned the lock of his door and opened it C oh,so gently! And then, when I had made an opening big enough for my head, I put in a dark lantern, all closed that no light shone out, and then I stuck in my head.

VOA: special.2009.05.16